I really enjoy Linux but I find myself having to keep Windows partitions around for software that specifically requires Windows.
Proton makes everything easier by automatically running game files through a translation layer, and it “just works” quite well most of the time.
Also VanillaOS can apparently auto-spin a container when you try to open a .deb or AUR package (this is my rudimentary understanding).
Setting up WINE/Bottles, etc. is above my pay grade.
Is it not possible to create an OS that just does the same thing as Steam but for the entire OS?
Installing Wine is easy in most distros. Making .exes open in Wine by default too. You can even make it so that Windows executables are automatically recognised as executables, so that running ./program.exe in the terminal will just work. I think ZorinOS tries to make Windows executables native-like, and for common programs it’ll even suggest you the Linux version to install instead.
The problem with lots of games is that you’re going to need workarounds, like DXVK, each with their own quirks. Bottles and Lutris will handle those workarounds for you, but it’s a multi step process.
For very simple programs, you can just open the .exe with Wine and it’ll run. You don’t need to use containers or a hundred different Wine prefixes or helper tools. Only for stuff like games and CAD programs do you end up needing helper tools.
You also end up needing to install runtimes for some applications, but if the setups of those applications don’t try to install those for you, those apps would also break on barebones Windows computers. Wine does detect stuff like Mono and their IE replacement missing and tells you to install them.
You could probably trivially build an application that keeps track of .exe files, maybe even paths, assigns them to prefixes and other stuff set up automatically, and ask you if it’s not sure. I don’t know what problem that would solve, but you could make it.