Cleaving the hardware support from the OS support is precisely why the PC ecosystem can sustain much longer support periods, because those are separate concerns. Yes, at some point BIOS feature updates will cease (although usually they will crank out an update for everything going back a decade+ if there is some major vulnerability) but that doesn't mean Microsoft or Canonical or Red Hat can't keep rolling out OS feature updates for another decade on the existing BIOS feature level. And while BIOS security updates are occasionally a thing, the attack surface is much smaller, just like the hypervisor reduces Xbox/PS5 attack surface too.
The problem with Android's model is specifically that it ties these two together, so when the SOC vendor or the phone vendor get bored, the OS updates also cease.
Google has been moving towards changing that, by packaging more and more things as Google Service updates/etc rather than OS updates, but fundamentally the Android model is like your PC not getting Windows 10 because the motherboard vendor doesn't want to package it in a new BIOS image. And that's different.
Sometimes there are genuine feature cliffs, like 32-bit support, or UEFI support, or Windows 11 starting to move towards mandatory TPM. But if the OS vendor is willing to live with the old BIOS feature level, the BIOS vendor or the System Integrator doesn't need to keep packaging the updates for microsoft.
How much more all encompassing can you get than that.
I assure that Apple never went out of its way to release firmware for the 1st gen Intel Mac Mini so it could work with Windows 7.
Windows 7 supported all of my Mac hardware - Bluetooth, gigabit Ethernet, wifi, and it found the IR sensor for the remote. I never tried to use it.
Even before that, I had more obscure x86 hardware - a 486DX/2-66Mhz “DOS Compatibility Card” for my old Mac that came with Windows 3.1 and had a built in Soundblaster card. I was able to our Windows 95 on it without any updated drivers from Apple.