writing desktop UI is really difficult these days. I mean i'm not saying it used to be easier, but the amount of technologies you can use to write a web application or desktop/javascript application and easiness of creation is overwhelming, while the amount of GUI frameworks stays the same, while some of them are decaying (no new version for a long time).

So we have objective-c/swift (new!) for macos, MFC for MSVC++, WPF/UWP for C# - all those for windows, and we have QT/GTK for Linux and de facto multiplatform. That's basically all usable at the moment, but GTK is heavy on windows/mac in my opinion.

New languages bubbling up from the opensource ground meanwhile do not offer many bindings for those above, while QT had made it hard to do any reliable binding at all, apparently...