Same issue. The game for some reason uses Proton-9 by default instead of nothing as it should on my configuration (runtimes be damned) or Steam Linux Runtime 1 as all other Linux games do.
Hello, someone took a look at this and passed along a note that this is the current intended behavior. A manual pin was put in place to make this specific game default to Proton.
There's a game bug detailed at https://gitlab.freedesktop.org/mesa/mesa/-/issues/5801#note_2987617 which needs to be resolved by a game dev before that pin should be re-evaluated. Also, #8217 is a secondary issue that could use a game dev's attention.
Players can use the per-game override if they want to test the Linux native variant.
There's a game bug detailed at https://gitlab.freedesktop.org/mesa/mesa/-/issues/5801#note_2987617 which needs to be resolved by a game dev before that pin should be re-evaluated. Also, [#8217](https://github.com/ValveSoftware/steam-for-linux/issues/8217) is a secondary issue that could use a game dev's attention.
I have experienced no such bug, but it's at least good to know that the pin wasn't unintentional. Not closing the issue yet since the game still fails to launch for me by default, but I have updated it to include Steam Logs.
Thanks for clearing a part of it up, though!
Replying to https://github.com/ValveSoftware/steam-for-linux/issues/12511#issuecomment-3626976220
I did send a email to team cherry about this but i'm just a random player... consider if is possible send you, as Valve/Steam, ask about this possible fix in the game
Replying to https://github.com/ValveSoftware/steam-for-linux/issues/12511#issuecomment-3626976220
I wonder if either of these issues have been fixed in beta v1.5.12301 (released roughly 12 hours ago) (I have never gotten the former and can't test the latter)
Now if that is a thing, it would also be nice to pin Worms WMD to Proton since the Linux version is completely borked, and is likely unrecoverable without a full-blown container or a game rebuild which is not gonna happen. The best I've gotten is seeing the first splash screen before the game core dumped, and that's without the forced Steam Linux Runtime, with which the game won't even do that.
I installed xcom 2 today, with nothing selected in the compatibility tab and still, the stupid Windows version got downloaded instead of the Native Linux
I hope it be a error, because is disgusting if now, native versions get swap to Windows version and all running through Proton... I'm 0% interested in use proton
Your system information
Steam client version (build number or date):
Distribution: Fedora Linux 43
Opted into Steam client beta?: No
Have you checked for system updates?: No
Steam Logs: steam-logs.tar.gz
GPU: AMD
Please describe your issue in as much detail as possible:
Here is an image depicting the contents of Hollow Knight's installation directory before and after enabling the use of a runtime:

Steps for reproducing this issue: