I feel like a large part of the group making who believe Linux is gaming ready doesn't understand that angle.
At this moment they make up nearly 1.3 million concurrent players. The rest of the top 10 games that do not have a linux port accumulate close to 0.7 million concurrent players.
For a lot of players, CS:GO or Dota 2 are the only games they play regularly, so linux is a viable option for them.
You'll see all kinds of posts showing Min/Max FPS and how Linux beats Windows at this game or that but you rarely see any mention of Average FPS because they're usually pretty awful.
https://www.google.com/search?q=CS%3AGO+audio+delay+linux&ie...
In any case, it's the game developer's choice and not mine. Yet another problem Linux has for developers is that there isn't always a clear choice and the flavor of the day may not be the best choice long term. That's why frameworks like Qt and Unity are so prevalent because they abstract a lot of the crap away.
The terms gamer and gaming community are used by people to lump anyone who plays video games into a small digestible nugget. There is no single gaming community and the sheer size of each of the countless gaming communities dwarf most other hobby or enthusiast communities.
Most people promoting gaming on Linux are so out of touch that they think having Tux Racer playable makes a Linux desktop computer a first or even second class gaming platform. Having The Witcher 3 or Tomb Raider on Linux is a novelty or a way to win brownie points.
I'm not a serious gamer by any means, my highest played game only logs 403 hours of playtime, I've see people with ten times that. With that in mind, none of the games in my top 10 list in terms of hours (~1800 hours) played are available on Linux.