Most people don't even know what an architecture or ISA is ;-) But in terms of usefulness people will want to be able to execute their tasks and if a program that they use doesn't work (be it because it doesn't have an AArch64 version or anything else) they will not find that very useful.

I think you were mostly pointing at Windows's ARM failure so far, which is fair -- a lot of applications simply won't run unless they make an ARM specific version or have a binary that happens to be compatible with the Windows built in x86 emulator