apple does not let you use your own app store MS does on the pc
I'm using a Mac right now and I'm able to buy software from other stores such as Steam, Itch, Humble, etc. There's even an open source Mac package manager. iPhone, sure, that's a walled garden.
Backwards compatibility is one of the prime reasons why X86 has lasted so long. Even today, a tremendous amount of software is 32 bit. Intel would be eliminating one of the primary reasons people still use their chips.
Apple completely dropped 32-bit support in 2019 and people got over it. You might be thinking 'well Apple has a small market share anyway', but they did the same thing on iOS in 2017 (the 'appocalypse') and there wasn't a mass exodus to Android. I think if Intel did this, developers would pretty quickly follow and they'd end up with an advantage over AMD a few years down the track.
Time is nature's way of making sure that everything doesn't happen at once. Space is nature's way of making sure that everything doesn't happen to you.