I mean to not have 32 bit support by default makes sense. It wastes disk space for nothing. On ArchLinux for example to have 32 bit support you have to enable the multilib repo, that makes sense because in most installations you don't need it.
Plus 32 bit software can still run if it's stacically linked or run inside a container. The only thing that doens't ship is the dynamic libraries for 32 bit executables to run.
Steam definitely can’t run 32 bit games under current MacOS. (Most of those games run under Linux Steam though; I’m hoping Asahi gets an installer working for my 16” M2 soon).
As I understand it, in Apple’s case 32-bit support was also negatively impacting development of Cocoa/AppKit due to some Objective-C technicalities.
I think probably the right way to handle 32-bit compat is well-integrated virtualization ala Classic Mode from OS X’s early days. When the user tries to run a 32-bit binary, boot up a minimal old copy of the host OS and run it there. It’s not as nice as running it directly, but I think that’s fine; it gently pushes devs to bring their antiquated software into the modern era while allowing users to continue to run it and keeps OS development unshackled from the past.
Plus 32 bit software can still run if it's stacically linked or run inside a container. The only thing that doens't ship is the dynamic libraries for 32 bit executables to run.