If by "mental illness" this graph refers to the effects on the mind of the person who study it, then it's dreadfully accurate.

I blame the release of both Factorio and Victoria 3.

I think a lot of people are misunderstanding what Proton actually brought to Linux gaming.

I had been running Linux exclusively for some moths in 2013-2014, and trying to get games to work on Linux felt like this : Wine is likely able to run it if you can found the right configuration, but good luck with that. I think the only game I managed to run without issues was Civilization 4, so I rolled back on Windows some time later.

Of course, Valve contributed to Wine, and projects like dxvk and others are major achievements (if a team effort), but that's not their main contribution. Valve understood that gamers may be somewhat more tech-litterate than other people, but that making games work on Linux should be easy. And that's what Proton was made for.

Nowadays, most games I buy on Steam work out of the box. I sometimes forget to check protondb before buying a games, and I rarely had an issue. Even if in 2018 you had to tinker a bit, you rarely needed more than to choose the correct Proton version (big up to Glorious Eggroll).

I think it's symptomatic of the situation of the Linux Desktop : technically, it's where it needs to be. But there is still a gap in accessibility and easiness. Tinkering is nice, but you should not have to do it to have something that works.