By the same metric c++ qwidgets is amazing to write UIs and by keeping everything in c++ there is easily less abstraction, I can easily navigate my code, not jump between two different systems. There really is no great reason why qml objects couldn’t be c++ classes/functions. Decoupling does what for me, but introduce more syntax, documentation, and learning curves. You should give writing a Kde6 Kirigami app a try and experience the absolute pleasure of adding another abstraction layer onto qml, c++ to muck things up. Qml is the cooler brother of Uic, but at least uic was optional.