> anything that can actually boot macOS almost certainly exists purely to break the macOS license agreement.

Apple provides a hypervisor framework that emulates a standard ARM64 system and macOS ARM64 kernels that run on it. This is how macOS on Apple Silicon virtualization works. It's not really Apple Silicon, it's boring standard ARM on Apple Silicon. Soon after Apple started shipping these kernels, before it was even announced, someone tried it on QEMU on another platform and found it worked just fine in single user mode.

The only catch is the macOS UI requires Metal, and paravirtualized graphics are implemented using serialized Metal passthrough. In other words, if you want to boot ARM64 macOS to a desktop, you have to implement Metal in your VM host.