WPF was stamped out by lack of dogfooding = inability to inspire confidence, and then Microsoft spazzing out with that clusterfuck that was the Windows 8 "Metro" bullshit.

Back when I wanted it to succeed, Microsoft was barely using it in any of their own apps.

Apple has used SwiftUI in their OS more than MS/Windows did, and there's quite a few apps on the App Store that -seem- to be made with SwiftUI.