There's a difference between "we'll test and support two color schemes" and "we'll design ui with parametrised colors, shapes and text sizes which can adjust to any change and still be usable". If we settle on bright/dark/colorblind mode selectors that everyone expects to be supported, I'm happy. I've seen themes in the past and there was always a few apps which just can't resize elements in the expected way, or the backgrounds don't tile correctly, or ...
Ok, then don't support it. But don't patronise me. Don't tell me I couldn't possibly wield the power of recolouring a piece of UI without hurting myself, and deny me the chance to even try.
But libadwaita hasn't taken away the ability to try? You can still load custom themes through GTK_THEME and specific CSS through ~/.config/gtk-4.0/gtk.css.
