But none of that was configured in one place, with every other program taking its lead from that central configuration. Instead, effort must be made to work through every program individually, customizing its color scheme.

> But none of that was configured in one place, with every other program taking its lead from that central configuration

that's definitely not my experience with KDE, I just have to set a theme on the system settings and 99% of apps take it (e.g. with this theme in my case: https://www.reddit.com/r/unixporn/comments/b49l7k/kde_sweet_...).

For any apps written using Qt, sure.

Would you be surprised to learn the configuration is not for Qt/KDE only? Check packages xsettingsd, kde-gtk-config and qtcurve.

that's how it has always been. There isn't a system out there that does theming where some apps won't be left out. It's practically impossible. Even dark mode on iOS doesn't work on every app. And then there is Android... which is just unspeakably bad at all things UX.