Linux.x64 is missing

after starting Hades Star on Steam I get this error:

many times I removed and installed different Steam (snap, flatpak, .deb)
always the same error.

1 year ago I was able to play that game.

That’s not related to KDE.

But from what I can tell, that seems like an error on the part of the game publisher (the publisher either didn’t provide the file or provided the wrong filename).