Well, every platform has its idiosyncrasies that you have to learn. No less with Qt, QML, and Flutter. You just take them for granted.
Cocoa/UIKit are my wheelhouse and have their own share of entry level StackOverflow questions. Though personally I think they make even less sense than the web toolkit. But if you just go by StackOverflow questions, you'd wonder if it was possible to learn anything.
Just search something like "auto layout" on StackOverflow. Turns out that client dev just isn't that easy no matter which abstraction you want to use.
I've done forms with Qt, QML and Flutter, and it's completely different experience.