I trust MS in this. NT has been multi-arch since day one. x86 wasn’t even the original lead architecture.

They also know the score. Intel is not in a good place, and Apple has been showing them up in lower power segments like laptops, which happen to be the #1 non-server segment by far.

They don’t want to risk getting stuck the way Apple did three times (68k, POC, Intel) where someone else was limiting their sales.

So they’re laying groundwork. If it’s a backup plan, they’re ready. If ARM takes off and x86 keeps going well, they’re even better off.