Honest question – how do you build cross-platform application UI in python?
The main hurdle that other languages faced was not having a native UI. For example, GTK on OSX or Windows did not feel native. Key bindings were often not native. Similar story with Java (was it Swing?).
The HTML/JS/CSS combo has exactly the same issue (it's not comparable to a native GUI - Cocoa or whatever it is.
Electron faces this same hurdle, but with a twist. It just doesn't care; it picks a rendering target (the web) and simply uses it everywhere. Perhaps that's the approach QT and others need to take as well: stop trying to match Apple's UI on Apple, and Windows' UI on Windows.
Great idea, but make sure it at least looks/feels good.
I remember Swing stuff from the late 90s and... IMO the primary issue wasn't so much that "it doesn't look like Windows" but that ... it was a very poor experience.
Copy/paste/keys - yeah, that's an annoyance, but if the UI is clean, friendly, easy to understand and be productive on, people can look past the differences of the native host OS. Swing (and GTK and others) really don't provide a 'better' UX (imo).