I have WoW for Linux version 0.5.3 alpha, compiled by Slouken, lying around somewhere.
Interestingly he also developed SDL and today works on WINE and Proton, and has thus directly helped bring the game to Linux by implementing the compatibility layer it runs on.
It is true that it would be nice with a real port but I’m just not seeing it happen. Sometimes a nugget drops here and there which clearly proves there is a Linux port created internally. We find commits made by Blizzard to wine to make sure the game runs, we find text strings in the game that mention the modifier key “meta” - which is how GNOME refers to the Windows key. WoW even uses the Windows API’s directly to shut down and alt+tab rather than implementing their own hard-coded bind, which means that in WoW you can actually keybind alt+tab and alt+F4 and use them when playing.
The Warden, although it runs as an .exe, has hooks into Linux. It notices Linux and starts running differently. We can see that on Linux.
It’s very obvious a Linux port exists. Very, very obvious. The state of it I do not know. I wish they’d release it, even if they slap an “unsupported” label on it.