UPDATE: I can confirm that Delphi 10.4.2 installs, builds and runs on a Mac M1 with a Parallels Desktop VM of WIndows 10 ARM (insider build).
I successfully installed all my components (TMS, JVE, custom), build and ran both VCL (win32) and FMX (win32, MacOS64, Android32/64 and iOS64) perfectly.
I'm going to keep using it for a while but if all goes well, this is a great solution and so much faster than my older Intel Macbook