> almost every game on Steam has a quick accessible rating that lets me know if it works fine on Linux
Sure, it's more convenient that Valve runs Steam and can put the rating right there. But let's give WineHQ a bit of credit here. They have a database going back more than a decade now, telling you how games run on Linux.
The effects of Valve getting into Linux gaming are definitely noticeable. But the Wine team deserves a boatload of praise too. I was playing World of Warcraft back in 2007 and it was a flawless experience.
> rush to get games ported to Linux actually is happening
I'm not really sure about this. By having Proton/Wine at such a high quality, most devs are just going to target Windows. Because why bother? They will probably ensure their games run good under Wine and that's where it ends. Nowadays I'm totally okay with that. Lutris is great, Wine is actually easy to use. It's the best time to be a Linux gamer.