All these types of frameworks, ones that have code to make their own UI are fine, but what I really want is to have a declarative UI, like HTML or XAML, bound with some user interaction event engine and access to the underlying OS.

Hopefully, we can have that someday, without the likes of Electron or whatnot.

I would like to write a react app, with all its progress in UI/UX and thousands of libraries, package them into a Python app and distribute it as a desktop application.