Some of us are still programming in Qt using just C++ and .ui files. Never bothered to switch to QML. I wasn't convinced there were enough advantages to make it worth the effort.
If I wanted, I coudl ask gemini to port the app to C++. (Gemini isn't the point here- that's just speeding up what I would have done on my own).
Examples: Autodesk Maya, 3DS Max, Mudbox Foundry Nuke, Mari, Katana SideFX Houdini Substance Painter, Designer