Not only that, they built an entire x86 and x64 emulator into Windows for Arm, so that (for example) if you install Parallels on a M1/M2 Mac and run Windows on it, you're getting the special Windows for Arm build, but many of your apps will still run because of the built in emulation of Windows.

It's just crazy compared to how much software just completely breaks between different macOS releases with no recourse, or have to be recompiled and reinstalled from scratch on Linuxes. Microsoft's bad at a lot of things, but they deserve a huge amount of credit for their backward compatibility on Windows...

https://learn.microsoft.com/en-us/windows/arm/overview

Edit: Seems that emulation system also uses WOW64! https://learn.microsoft.com/en-us/windows/arm/apps-on-arm-x8...