Once KDE 6.8 is released, Valve must add Wayland support for Steam client and Proton/Wine. Also, they should drop 32-bit dependencies for Steam client on Linux, which has been done for Windows and macOS long ago.
+1. Most games, once shipped, completely disband their development team.
If you require game developers to even so much as recompile their game, they simply cannot do it. If you want the game to keep working, you have to guarantee ABI compatibility in perpetuity.
I'm in favor of removing 32-bit dependencies from steam-the-application, except that you still need 32-bit libraries to run 32-bit games in Wine.
Having steam depend on those libraries directly means that when you install you get all the libraries you'll need and you won't run into issues later on when you go to run a 32-bit game and it can't load the appropriate 32-bit system libraries for you. It's annoying for sure but it simplifies the user experience dramatically (especially if you're just installing Steam directly on Ubuntu or something).