A lot of the items that GP and you are discussing are, from my perspective, complaints about Linux circa 2005, maybe 2010 in a few cases.
I do all the above things and problems are rare. To the point where I ditched my Windows install for gaming. Steam's work on Proton means games seem to just work with the exception of specific Anti-Cheat software in certain games (and even in those games it's usually just MP that doesn't work).
KDE Plasma gives me basically the Windows 7 desktop interface with whatever window dressing I want and virtual desktop support out of the box. Plus, I can do everything that Linux can without any Windows overhead.
Maybe I'm really lucky re: productivity stuff but honestly I don't have a ton of complaints about it.
Thanks to Valve's Proton, now most Windows games work flawlessly on Linux. When you install them from Steam, you don't even have to know they're Windows binaries, they just work.
I think it just comes down to how you uses a computer. I mainly program, web browse, and listen to music. I don't game, watch movies, nor use or want to use 'business' apps. Abiword is about the most business app I use with any regularity. If I -have- to do something else, usually GDocs can handle it.
Re: 5) It might depend on the person. I've only ever used Gimp, and while it has redone the UI multiple times, and some things remain nonintuitive, I find myself around it well enough. When PhotoPea launched with its PS style UI, I wanted to give it a try to see what I was missing. I find myself lost, probably how a PS user feels going into Gimp.