Right now it's relatively straight forwards to run say, Windows or Linux under virtualisation. The reason this runs so well is because the actual instruction set which in this case is x64_86 (i.e. Intel or AMD) remains the same, you are just using a hypervisor to manage and segregate the different virtual machines.
The key difference once you switch to Apple Silicone is this is no longer using the same instruction set, and instead uses Arm as opposed to x86_64. Its not all bad news as you can already emulate x86 code in the Arm version of Windows, and Microsoft have recently announced you will soon be able to do the same with 64bit applications as well.
I think with a company as large as Apple opting to move over to Arm architecture, its really only a matter of time before the likes of Dell, HP and Lenovo start to do the same and the more people adopt the platform the faster it will be for applications to be compiled natively for other architectures besides Intel/AMD, and over time the requirement to run 64bit Windows installations will simply become less important to people.
But for now, I really wouldn't expect the full emulation of 64bit Windows 10 on Apple Silicone to be an overnight thing.
