City skylines has more than filled this gap imho. Great community. You should check it out if you haven’t yet.
SimCity on the other hand is challenging to keep going throughout. You need to make thoughtful choices on what you're building next and where or else due to some quirk of the Agent system you're going to be on the brink of collapse (Why won't the power go down this one street??)
Obviously there's room for improvement on the SimCity front, but my point is that if you're looking for a challenging city builder, Skylines is not it unless you wanna spend time configuring mods.
Sounds like a great selling point to me.
But not for me, that's not what I'm looking for in a city builder. Different strokes.
I'm so glad City Skyline had such a success, because I feel that other Paradox Interactive games wouldn't have existed otherwise.
As an avid player of Stellaris, and as someone eyeing the Crusader Kings series or Europa Universalis, I'm feel that Paradox games have DLCs done right. They are clearly on the expensive side, but they are contentfull, and feel less shameless than EA counterpart (especially with the Sims who has the same DLCs over and over again).
On a side note, there is also Caesar III (& Pharaoh) on Gog, and it's still a gem.
I mostly said that because of a gut feeling that CS is their main cash cow, while their others series are solid but with a more niche player base.
Might have been so in the past, but Paradox games are relatively mainstream, although they seem a bit niche.
Hearts of Iron IV is the 32th most played game at Steam right now (https://steamdb.info/charts/), while Cities: Skylines is on spot 56. Might have something to do with recent news or released addons, but still, other Paradox games are wildly popular and Paradox would surely do just fine even without Cities: Skylines.
More interesting stats comparing Hearts of Iron with Cities: Skylines
> Cities: Skylines - 18,280 players right now | 24,541 24-hour peak | 60,386 all-time peak 8 years ago
> Hearts of Iron IV - 32,652 players right now | 44,193 24-hour peak | 70,997 all-time peak 5 months ago
Really night and day in term of bugs. Idk what they did, better hire, better process or more people on it (or all 3), but it made multi-player bearable on EU4, and great on Hoi4/stellaris (I do not like the game that much, but it's a better MP game than EU4, let's be honest.)
Anyway, Hoi4 isn't niche anymore. It's like top5 MP strategy game.
The games Paradox itself develops are the grand strategy games in the Crusader Kings, Europa Universalis, Hearts of Iron, Stellaris, Victoria, and Imperator: Rome lines. The flagship games here are the strongest games in the genre, and even among the broader category of strategy games, they're definitely in the most-played games, with the main competitors being the Civilization, Age of Empires, Total War, and Mount & Blade series.
Probably parent meant the developer of the game, Colossal Order, which only developed Cities in Motion before, which was successful in it's own right but not on the scale of Cities: Skylines. But then "other X games wouldn't have existed otherwise" doesn't make sense, because Cities: Skylines is the latest game they've launched, and it was in 2015.
But it's a great city building simulator.
Other than that, you can see what's included with every DLC on the C:S wiki: https://skylines.paradoxwikis.com/Downloadable_content. That way, you can decide which DLCs you care about and which you don't.
They do occasionally go on sale, so you can always just wishlist something and come back later.
Mass Transit is a joke, all the options are just memes.