Hello @D-357, game updates are handled by the Steam client, not Proton itself. You are most likely using the Steam client beta and encountered https://github.com/ValveSoftware/steam-for-linux/issues/5901 as a side effect of "Fixed an issue with invalid Steam Play tool selections if user had previously opted in to enable Steam Play for all titles. (Note: this will cause a one-time reset of all Steam Play global and per-app selections to the default state)." in the 2019-01-18 Steam client beta update.
Closing as out-of-scope for this issue tracker.
I usually only get one game updated, which I think is strange because I thought all games received different updates respectively from wine/proton (how ever it works). Anyway the size of this download is just odd to me.
