Theres a new, minimal, cross-platform native app framework called #Fyne for Go that is pretty impressive and something I think most of my mutuals will be interested in. It solves a lot of the same problems as #Flutter, allowing you to write native apps for mobile and desktop seamlessly, while being much more lightweight and using a language that is well designed and nice to use. And it's not GTK based, it implements its own renderer. They are creating their own desktop, which has a very similar look & feel to #xfce, and the vibe of the project overall seems to be shooting to cover much of the same needs as GNOME but much more minimal and emphasizing no-nonsense mobile & desktop development.
Not many offerings check all those boxes, and those that do tend to be on the McDonalds end of the software spectrum.