He is using Wayland, but back in U22.04 it was relatively unobtrusive. Recent Gnome releases often have only two themes out of the box, dark and almost dark. Heavy black title bars and zero width borders.
Well behaved gtk2 lazarus apps use only the colors from the current theme, while theme sets typically have ten or more possible colors, in Gnome in particular, most of those colors are the same. And dark.
So, a black rectangle on a black background with zero width borders ....
Gnome is keen to 'simplify' the UI. Canonical is still pining for Unity, an OS designed for a phone, so, rich widget sets like we love in Lazarus, depending on detail, are just not catered for.
gasensor, try Mate, Budgie, Cinnamon, XFCe etc. Not only will your Widget sets look better but your negative mood may improve as well.
Davo
edit: typo (mood v mode)