3-4 years ago it wasn't difficult at all to replace macOS with pretty much any EFI-enabled OS. Moving to a proprietary ARM CPU/GPU will probably result in not being able to write applications unless it's using Apple's toolchain. If you have no say over what software you can run on your computer, you no longer own that computer.

We really haven't seen such a large technological separation like this. At least back in the old days you could still run what you want.

macOS moving to the iOS route where you have to jailbreak your device to get any sort of usability out of it is not a space I want to participate in, and yet it seems that's how the entire Apple line is moving. They're almost the complete opposite compared to Microsoft these days.