I anticipate that ARM macOS will not run at all on systems without Apple Silicon (as they are calling it) and never will. I assume these systems will have the proprietary secure enclave on-die, which would be missing from all other ARM systems.

Hopefully I am wrong.

I agree. No one has ever managed to get iOS on non-Apple hardware†, and I don't see why ARM macOS would be any different.

† Except maybe Correllium, which was a large commercial effort. Since they don't make any details public, I'm not clear if Correllium just built a sort of emulator or if they actually have the OS running "natively" on 3rd party hardware.

The Darwin on ARM Project[1] attempted just that. It depends on what you mean by "iOS" if you want to say they accomplished it - for example, they got XNU, the kernel, running on a Nokia N900, but they never got a UI up and running (only single-user mode).

[1] https://github.com/darwin-on-arm

It’s using hardware virtualization for the CPU, but emulating peripherals, similar to your average VM software.

Well Mac OS X never could run on AMD CPUs and yet the Hackintosh community patched parts of it to get it to run.