I’m not that advanced to give you a good answer here but basically some UI and backend elements from GTK3 don’t exist in GTK4 and the last one has more limited theming support. The biggest issue is probably the random deprecation and breakage of older things during minor updates of GTK4. This all makes devs use GTK3 instead and not upgrading to GTK4. It’s old, stable and feature-rich
I’m not that advanced to give you a good answer here but basically some UI and backend elements from GTK3 don’t exist in GTK4 and the last one has more limited theming support. The biggest issue is probably the random deprecation and breakage of older things during minor updates of GTK4. This all makes devs use GTK3 instead and not upgrading to GTK4. It’s old, stable and feature-rich
Note: much of the benefits and downsides of gtk4 you mentioned are actually libadwaitas up and downsides.
Well sorry. I’m not a backend dev
This is misleading. GTK4 is very themable.
However many projects use libawaita which forces a specific style, in order to design a complex and well integrated UI.