From my understanding, what you’re suggesting requires emulation, so you’d probably need another operating system underneath; there are translation layers for other architectures, like Apple has with Rosetta and what WINE did for Arm, but it sounds very challenging to implement something like this for executables of the actual operating system which can operate at a very low level. So I guess this is in the theoretical realm. Maybe someone is mad enough to do this, but I wouldn’t expect it.
It depends. Microsoft has recently enabled compilation options for their binaries that will make them incompatible with older CPUs: https://www.guru3d.com/story/windows-11-24h2-new-cpu-instruction-requirements-impact-compatibility-on-older-hardware/
Granted, these are quite old nowadays, but they could enforce newer instructions as well, like AVX-512.
Wouldn’t it be possible to emulate these new instructions? It would definitely hinder the performance, tho.
From my understanding, what you’re suggesting requires emulation, so you’d probably need another operating system underneath; there are translation layers for other architectures, like Apple has with Rosetta and what WINE did for Arm, but it sounds very challenging to implement something like this for executables of the actual operating system which can operate at a very low level. So I guess this is in the theoretical realm. Maybe someone is mad enough to do this, but I wouldn’t expect it.