>>106585390
>The KDE ones work fine for me. I'm not sure how standardized DDC/CI is, but it could be that wayland or whatever compositor/wm you use doesn't support your screen's brightness control interface.
It is the standard, pretty much every monitor supports it nowadays.

KDE also implements a software brightness control for displays without support for hardware control though, so probably you should go bug your compositor developer to expose similar functionality.