This is why I've been all in on Steam for so long! The catalog is so huge, there's a massive number of fantastic couch multiplayer games. It is indeed a bit more fiddly... I've found that it's generally easier to connect my Steam Deck to the TV and play lower fidelity games than it is to fiddle with a Windows machine that needs to be prepped for friends popping in every other month.
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.
I used to rally friends over for couch gaming years ago. Think I'll try to put something together for Thanksgiving. Been a bit out of the loop - any recent PC couch games you recommend for normies? I think for my group, it'll lean casual / co-operative. Nintendo's always felt too kid-like for us.
"It takes two", "Split Fiction" and "Lego Voyage" are the same style of casual two-player coop. Downside is it's only two players but otherwise may he exactly what you're looking for and very well made.
If you want something a bit different, check out "keep talking or everbody explodes".
Rivals of Aesther - like Super Smash Bros but with Steam Workshop support for player-made characters... TARS (interstellar) vs Ronald McDonald vs Obama anyone??
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.
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.