Right, Windows NT was shipped on PowerPC, MIPS and Alpha up until 1999; Then MS shipped Windows Server on IA64 Itanium from around that time right up to 2010, alongside the x64 version - including shipping IA64 versions of .NET, SQL Server, etc. And they began shipping Windows on ARM with WindowsRT in 2011.

I actually don't think there has been any significant period where Microsoft was only shipping core Windows operating systems on only x86. It's possible that's actually a deliberate strategy.

But to your point, what they have never been able to do was persuade any significant part of the ecosystem to notice.