Consoles purposefully add a big barrier for indies, so that doesn't help. I'm sure many devs would love to support console but lack the resources. I can't think of a single AAA/AA game that is PC exclusive.
Well, I don’t own a console, just a Mac. There are a number of games on Steam I’d like to play, but they are PC only. Perhaps they are also available on consoles, but I wouldn’t know.
Macs have many of the same problems as consoles with exclusive SDKs and custom graphics stacks (Metal) but without the benefit of the console manufacturer working to make it (relatively) easy to make and sell games on their platform.
Really depends on the game. Aside from my multiplayer shooters, I played all my games on Linux. And these shooters would work too, if not for the pesky anti-cheats. If you'd like, you can check if the Steam game would work on Linux with this tool: https://www.protondb.com/app/1174180
I'm personally using Debian testing with KDE, but as long as Steam works, you should be fine. Zorin is also a nice out of the box experience.