[...] The best way this could be achieved would be if someone released a product which went beyond virtualisation and also emulated an Intel processor. This would be similar in concept to products like Virtual PC (from Connectix, later bought by Microsoft) which emulated an Intel PC down to the processor instructions, and allowed running DOS or Windows on a PowerPC Mac. [...]

Certainly the priority, for Fusion, is to virtualise ARM on ARM, on M1 Macs (and of course continue to virtualise Intel on Intel, on Intel Macs): but in the future, it would indeed be interesting to have also an emulator product with a decent speed (as Connectix/Microsoft Virtual PC was), especially for OS enthusiasts/hobbyists. The main problem, here, is that current emulator solutions are not optimised for Macs and also too slow to be really usable: so, there would have to be some solution that improves all this - which isn’t certainly easy! Anyway, on the Windows and Linux front, being limited to ARM virtualisation probably won’t be a problem (Windows ARM version will be able to run also x86/x64 applications and Linux will be native also on ARM); while being able to run, for example, old versions of macOS will require emulation (if Rosetta 2 won’t support Intel virtual machines)...