Even if that happens, I'm not sure how much appeal an ARM version of Windows actually has. Right now, the only things keeping me on Windows are Visual Studio and my huge library of legacy software (
ahem video games). Microsoft's x86 emulation on ARM is downright atrocious. A native ARM version of Visual Studio could keep me productive, but I'm not about to spend money on a new computer than runs all my favorite old games noticeably worse than my current machine.
If I buy an ARM machine any time in the next 5 years, it will almost certainly run macOS or Linux, with Windows relegated to an x86 box that I use for gaming.