Although, Nintendo is still doing a good job at keeping the couch-social experience alive, and building 1st party games that can be good solo experiences but really shine when played next to a friend sitting on the same couch.
The Trine series was a big hit for us way back.
If you want something a bit different, check out "keep talking or everbody explodes".
nidhogg - deserves to be in an arcade cabinet but honestly this one is ALWAYS a hit...just 2player though
Broforce - 80s action stars in 80s action movie multiplayer platformer
Ultimate Chicken Horse - competitively build a platformer level and then race to complete the level first, best with 4 players
TowerFall Ascension - 2-4 players, also deserves to be in an arcade cabinet
Screen Cheat - FPS made for the couch; think N64 Goldeneye or Quake, but all the players are invisible, so the only way to figure out where your opponents are is to look at their quadrants (screencheat)
Overcooked 2 - it's pretty kid-oriented on the surface, but it's a game where you must out-communicate the absolute chaos unfolding around you in order to succeed...such a good couch-multiplayer experience, but best for experienced gamers imho
Rocket League
Magicka
Regular Human Basketball - control giant basketball automatons by jumping inside them and operating the manual controls in a team v team. Minimum 4 players to really work well, supports up to 10 players shared screen
That should get you started! But oops that wasn't my casual coop list, more my "makes for memorable group experiences" list.
It Takes Two, Portal 2, Untitled Goose Game, Halo Master Chief Collection was like $10 recently, all come to mind as positive local coop experiences I've had.
We enjoyed Split Fiction and It Takes Two recently, but those are quite couple-y. And Blue Prince is very playable as a group effort.
Then there are games like “overcooked”, though again not many. IIRC there’s a new Katamari on the way as well.
But there really aren’t that many “get your mates together” games any more.
It's especially fascinating against the lens of this return-to-office phase we're living through. I'm a big fan of WFH but hear me out: online gaming (physically by yourself) is somewhat analogous to work-from-home. It empowers you to optimize your entertainment, challenge, competition into narrower and narrower facets of the experience. And tribe.
But jibba jabba around the water cooler can be enjoyable with the right people, just like it can be on the couch with friends and fam with Mario Kart, NHL '97, or Jackbox. Or board games.
There's room in this zeitgeist for a breakout multiplayer hit that just doesn't feel good unless you're in person.
But there's still plenty of couch co-op games. They're usually quite niche though and not your typical racing or shooting game.
What's the point with a console then though?