sorry to continue on old topic, but as experience shows Microsoft is pretty slow on the development lately. They just released support for UWP in .NET 9. There are some adjustments to do, but they promise that UWP API is available as before, no new features though (except supporting still the UWP technology stack on .NET 9, since it was based before on .NET Core 3.1 that is now out of service (since December 13, 2022).

It requires last update of Visual Studio 2022, v17.13. https://learn.microsoft.com/en-us/visualstudio/releases/2022/release-notes#desktop