True, but ARM, and apple in particular have been willing to discard compatibility with previous generations. I believe the M1 for instance is not 32 bit compat

True, but ARM, and apple in particular have been willing to discard compatibility with previous generations. I believe the M1 for instance is not 32 bit compatible. ARM also was willing to do some house cleaning when they designed the 64 bit architecture. X86-64s on the other hand have compatibility not just to 32 bit, but also 16 bit. You can still boot dos 1.0 if you wanted.