Except Apple keeps their hardware locked in the Apple ecosystem, but anyhow can buy AMD or Intel
You can already get a usable desktop on an M1 Mac, if you really want to. The CPU is fast enough that you don't absolutely need graphics acceleration, and Wifi, USB, and display output all work.
The big missing piece is the GPU, but Alyssa has a fully-custom user-space implementation for macOS that largely works.