Wow can be played on WINE. I haven't tried it since WINE 2.0, but with WINE 1.9.x and Legion, it worked without a performance penalty when using OpenGL. Unfortunately, Blizzard's implementation of OpenGL is buggy, and since it's not a supported API, they're not improving it (by their own admission). Artifacts and visual glitches abound, and it's the same running WoW in WINE and in Windows with OpenGL (so it's not WINE causing the artifacts). It's playable, but it's not an ideal situation.
WINE can still run WoW using Direct3d without the visual artifacts, but there is a significant performance penalty incurred translating the D3d calls to OGL. I had to reduce the visual detail significantly compared to my Windows installation to get a similar frame rate at the same resolution (1080p). Again, it is playable, but not ideal. I'd certainly do that before going to Windows 10, but not everyone despises 10 more than they appreciate or desire performance.
I think this is fairly representative of the Linux gaming problem in general. It's the APIs... if Windows games ever used an API that was also native to Linux, WINE would run just about all of them without a problem, and with performance that is pretty close to that of Windows. Devs don't really have to release Linux versions of games to make Linux gaming viable... they just need to release them with an API that's available natively in Linux (which would be part of releasing a completely Linux native game too). Gamers, and particularly those who use Linux, will figure out how to get it to work once the APIs are in place. It could the begin to snowball, and perhaps get to where Linux native versions of games are economically feasible.
Biting the hand that feeds IT
