Unfortunately Microsoft has been all over the place with their dev technologies lately. We certainly have had our own struggles trying to plan and roadmap our own apps given their tendency to just axe entire product lines via press release.
With the Runtime SDK for WPF being retired and given the state of the Xamarin/.net MAUI transition the last couple of years ESRI's decision to go the WSA route is understandable. With .net MAUI now approaching something resembling production-ready it might be the best path forward to bring Field Maps back to Windows tablets.
They totally had the rug pulled out from under them with this announcement, but my hope is that if enough customers can demonstrate the need to continue Field Maps on Windows they'll be able to devote resources to a .net MAUI implementation.
Personally we only use Windows tablets with Field Maps for field work in secure locations that don't allow cameras (iPads). This represents a tiny but important fraction of our usage.