I feel like the best option at the moment is egui. It's native. Works on the web too. Very easy to get up and running. The things I don't like about it:

I personally think the default style could do with improvement. Mainly it's way too cramped. There's a happy middle ground between no padding and bootstrap. I mean Win32/Qt/etc. got this basically right.
Immediate mode. Yeah it's easier, especially with Rust, but ... it's surely not how it's supposed to work.
The low level drawing API (like if you're making custom widgets) is surprisingly amateur. Not something I'd want to target if I'm spending a lot of time e.g. writing a custom map widget or git graph or something.

I also tried Slint. Like the author I think the license is pretty reasonable. But it is pretty involved to set up a project and since it compiles everything from source it can take a very long time for a clean build of hello world. It's like if you were using Qt but instead of a binary package the sources are just included in your app.

Also I have bad experiences from QML (Javascript 🤮, weird scoping rules, etc.) but hopefully they learnt from their experience.

Looking forward to the 2030 edition anyway!