New Battle.net update Version 14542 breaks Linux compatibility with Wine/Proton via Lutris or Steam and will only display a gray screen.
Workaround is to delete the update folder Battle.2.net.14542
under $wine_root$/drive_c/Program Files (x86)/Battle.net/
and then start the client again.
Update workaround: Set WINE_SIMULATE_WRITECOPY=1 environment variable in Lutris
I don’t know if blizz ever cared about people playing their game on Linux in the past, but msft titles on steam are often the ones I have the most compatibility issues with. I don’t think it’s deliberate so much as I think msft just likes to invent and use new windows specific dependencies that often break wine.
I know valve’s push on Linux is a direct attack on windows’ monopoly on gaming, so it makes sense that msft would make at least some effort to make gaming on Linux as unpleasant as it can.