Even if apps require macos 14, it looks like it is supported on machines going back to 2018 for the most part:
https://support.apple.com/en-us/105113
I suspect that Macs will reach back to M1s for quite a while.
When I had a job writing mobile apps, I tried to "fight the good fight" by keeping our minimum version as low as possible, but everyone up the chain from me pressured us to increase it, especially software engineering, because it was "too hard" to maintain backward compatibility with older versions. Even though maintaining compatibility usually just meant a handful of if statements.
If we're talking about OSs alone, Windows wins. MacOS/iOS second. Android dead last on average (but it's much better now on some new phones).
You can easily run Windows on a PC from 2010 (at least on a desktop PC with a good CPU), getting updates well into the 2030s...