I could technically plug the PC to the TV but I don't know if it's going to provide the hassle free comfy experience consoles do.
I built a PC specifically for the living room last year, I boot it into Steam's Big Picture mode, for controller only user interface.
99% of the time it has been as hassle free and comfy as consoles.
The last 1% of hassle comes from having to pull out a keyboard with touch pad to navigate a mouse pointer when upgrading Nvidia drivers, when installing mods from Nexusmods, when installing and adding Gamepass games to Steam, and even if rare there are games that lack controller support.
If you can handle the higher cost I'd say it's worth it. Better visuals, better performance, mods, and it can become that one box that does it all. I play Steam, Epic, Gamepass, PlayStation, Xbox games on it.
And that's why I place my vote on:
On the couch w/ PC
I play some games on another regular PC with mouse and keyboard, like first person games and point and click strategy and city builders and also Diablo.
So my #2 choice would be:
On the desktop w/ PC
But in general I hate WASD controls, it's essentially digital 80s arrow keys controls, just awful imo. So for me it's the mouse aiming that's pulling me to the desk, first person aiming with a mouse is ten times better than using an analog stick.
Switch 2 with analog stick movements in left hand and mouse aiming in right hand is going to feel like a revolution for me.