I’m always wary of MacOS upgrades from when Snow Leopard made my Warcraft and Age of Empires stop working. Ultimately, I find it best to just suck it up and upgrade and use virtualization to run specific stuff. Mac is the easiest for me to have a daily driver browser while also being useful for most dev and basic Unix user tasks.
Unfortunately Apple has lousy backward compatibility, particularly for games. Dropping 32-bit is going to kill a bunch of games. On iOS it seeem even worse, with yearly releases breaking many apps; Apple's aggressive ABI changes offload a large maintenance burden onto app developers, who have to keep updating their apps every year just to keep them working the same way. Windows seems to do a lot better, and game cons…
Ideally, apps that work on one iOS release will continue working on the next with no change in behavior, as Apple checks when apps were linked and will opt out of the new behavior.