I was about to make a new issue about this
it's too bad that we have to set launch option for gamemode for every single game
a global option and per game option on steam about these stuff would be great
however no one cared about this one no one from valve and no one from community so i guess there is no hope
Nothing extracted yet.
Given the problems of some linux ports and proton emulations, i would reassume important per game settings that would be very very useful to introduce in the game configuration page:
This should be performed also via BPM (along with "enable steam overlay" and use proton for unsupported games).