There are still niches for specialized audiences, like historical battles with a more strategic bent, but for mass market RTS nothing has been able to beat a 23 year old game.
> It's basically the perfect RTS so everything that came after it seems inferior. Even Starcraft 2.
SC2 had a bunch of design choices that seemed to reflect a shallow understanding of what made BW actually super good. Like, how incredibly tightly units clumped together should've been picked out as an obvious flaw immediately, but instead they never fixed the underlying issue and just patched up some of the negative impacts via econ changes.
Pretty much everyone who used air-units in SC1 abused the "tight" formations of Muta-stacks (or other SC:BW air units). In most fights: tight formations are incredibly superior to loose formations. (Obviously Corsairs / Valkyries changed that, but typical hit-and-run tactics are better when stacked)
Automatically having tight stacks in SC2 meant the skill-curve of tight formations was brought down: so that beginners can benefit from the strategy with less practice. Advanced players can still use their superior APM to loosen the formations (if they go up against anti-death ball units, like Siege Tanks or Banelings).
In contrast to Brood War, where battles tend to unfold as an aggregate of smaller engagements happening simultaneously all around the map, Starcraft 2 hinges a lot on positional play with two giant armies dancing around and probing each other trying to engage at an advantageous position. And then once they get drawn into an engagement it's just BOOM! ZAP! POW! and it's over. If you blink you could miss it.
In the ZvT metagame, Zerg can deploy Mutalisks many minutes before the Terrain have access to Valkyries (AoE anti-air). Terrain's only response at that stage in the game is Marines.
Marines (who shoot one-vs-one) need to group up tightly to have a chance vs Mutalisks. However, a Marine only has 40 HP, and can be KO'd by a group of 11 Mutalisks taking one shot simultaneously.
This forces the enemy Terrain player to group up their Marines before approaching Mutalisks: the Mutalisks are flying however, so they just run away when they see the opponent grouping up. By forcing the opponent to group up, respond, and deploy, you win the "APM / Clicks" war. You're just trying to force the opponent to "waste their clicks" and eat up their mental capacity.
If the opponent fails to respond, you just run into their economy and destroy their workers. If you break the opponent's economy, you pretty much instantly win. Because you have flying units, you always have access to the opponent's backline / economy. (IE: most Terrain players "wall off" their economy so that ground units must destroy a 500HP defensive structure before reaching the backline. But you can get around those walls by using flying units, like Mutalisks)
Otherwise, you take advantage of map features: high-ground makes your creatures invisible (even air creatures are invisible on the high ground in Starcraft: Brood War). So you swing in from the cliffs / retreat into the cliffs repeatedly.
A missile turret has 200 HP, and is a bit harder to deal with. However, a Muta-stack with of 11 can KO the missile turret before it even takes a 2nd shot. It takes much practice: you need to learn the timing of the Mutalisk, carefully watch their animation and positioning (they only take a "instant shot" if they're flying in the same direction that the shot will take place), and Mutalisks can instantly turn-around (you need to move-click 180-degrees offset from the direction of their current movement).
With accurate timing, you can move-click, attack the missile turret, move-click away (causing an instant turnaround, leaving the missile turret range, preventing the 2nd shot), then move-click attack the missile turret a 2nd time and KO the defensive structure. This is the "muscle memory" practice that made Starcraft: Brood War famous. Only those who dedicate many hours of practice to memorizing this strict timing will even reach the barebone basics of the game.
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Eventually, Terrain can go Valkyries and with a large enough group, can AoE kill the entire Mutalisk stack. However, that's later in the game. By that point, the Zerg player has moved onto their main strategy (probably mass ground-forces, like Hydralisks). Valkyries are useless against that, and its well known that Mutalisks are otherwise an inefficient unit in combat. So its unlikely for the Zerg player to heavily invest into Mutalisks.
Whether intentional or not, I think 12 unit select was one of the design choices that enabled the pros and experts to really separate themselves from the average folks.
Starcraft 2 units really do "what you want" most of the time: automatically balling up into groups or "dancing" together. From one perspective, elite Starcraft1 players who memorized "The Magic Box" and other engine-level pathfinding behaviors saw this as an abomination: other players can gain the same skills now without practice.
On the other hand... lets be frank. Dragoon / Goliath pathfinding was bullshit from Starcraft1. The extraordinary measures you'd have to take to become a competitive player who uses those (ie: Magic box memorization. Dragoon Dance practice. Etc. etc.) was fundamentally unfun.
This is coming from me: someone who did put in the effort to properly dragoon dance / Muta stack / etc. etc. We all do things to seek a competitive edge against our opponents.
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The work / reward ratio needs to be there in some extent. But it can't be so large to turn beginners away. I'm not sure if anyone's found the proper balance yet, but Starcraft2 definitely was better from that perspective.
EDIT: I'm also a big fan of fighting games. Hyper-fighters, like Blazblue or Guilty Gear, have a nice auto-balance called combo proration. Combos are clearly the best way to play, but each combo makes the rest of the combo exponentially do less damage (!!!). This means that a 50 hit combo in BlazBlue will probably only do 10% more than a 20 hit combo, despite the huge difficulty curve in executing. The bulk of the damage is from the attacks before proration kicks in. This allows for the expert-community to practice for those 50-hit combos, while not necessarily granting huge 250% bonuses over beginners. A casual player may only decide to learn the 20-hit combo and still be 90% of the way to playing like an expert (compared to experts who have to work far, far harder to get the last 10% of damage).
While neither game is perfect IMO, letting the game mature without micromanaging it was a very important aspect of SCBW's success. Instead of mucking with units on a monthly basis they let things simmer and ultimately let balance be achieved through proper map design used in the competitive scene.
In my personal opinion one of the biggest faults with SC2 was their unit design philosophy. The idea that every unit was viable or had some special unlock created a balance nightmare. Its been years since I played either game competitively (played iCCup in BW / Collegiate StarLeague for SC2:WoL) but I remember always feeling like the game had too much "gotcha" in it that SCBW never had. Didn't scout proxy reapers? gg. Didn't scout fast void? gg. Didn't scout x? gg. It was too much rock-paper-scissors where missing one piece of intel was death while SCBW wasn't entirely the same. Taking the Terran/Protoss matchup for example you'd typically expect the early game to be vulture+tank vs. zealot+goon where if the terran player just a-moved into the protoss it was guaranteed loss, but microing the vulture and tanks gave you the chance and arguably the upperhand where the skill of the either player determined the outcome. SC2 didn't have that to the same extent.
So SC2 starts off with SCV-auto split, no more manual splitting at the start of the game (all players now can play the first 5-seconds of every game like a pro: no practice needed anymore) But then muscle-memory people wanted an edge, so they added MULEs / Spawn Larva / Chronoboost, giving players a muscle-memory / simple timer countdown to play with. Etc. etc.
Just back-and-forth changes like that was the real problem. The general balance patches had no idea for the final metagame they were actually going for. Did Blizzard want a game that rewarded manual effort (Juggle MULEs?)? Or did they want a game where manual-effort was minimized (Auto-Worker Split?)
In the end: Blizzard wanted both, even if the two designs contradicted each other. You really can't please both groups of players, but by switching back and forth between the two designs, they only really pissed off both camps over the long term.
Starcraft 2 added "Archon Mode", where you can 2vs1 (Weak+Weak player vs Strong player), controlling the same team. There were far more opportunities to play teams in Starcraft2 than Brood War.
And the 2v2 was always an option in Starcraft 2 anyway.
There's nothing dumber and more immersion-breaking than watching 15 dragoons get stuck in a small opening because the game's pathfinding is the very best the mid-90s has to offer. Or watching a reaver's scarab just ... get stuck, on the way to a target. They solved all of this crap (and a whole lot more) in SC2, and I can't go back.
I wish people would do this today. Release your game and let the rules be the rules.
Last year, Magic: the Gathering announced "by all our metrics, we consider the metagame healthy. So we're doing something we've never done before: we're banning a bunch of cards purely for the sake of change."
The overall market killed the RTS genre because everybody has a pretty clear idea of exactly how much money you're going to make selling an RTS and it's not that high. RTS games don't port well to consoles or mobile, and that's the majority of people and revenue.
Blizzard killed the RTS genre by completely optimizing for e-sports click-fests at the expense of everything else. A pox on their house.
It's PERFECT!