I see a lot of questions on the internet on “how do I control monitor brightness on macOS?” and a lot of “just use Control+Brightness Up/Down” answers from people not realizing that only Apple vendored monitors support that.

And that’s only possible because Apple implements a proprietary USB protocol inside their monitors for changing brightness so they have smooth transitions and be sure it works every time.

I’m pretty sure they’ll never touch DDC/CI for that, and rightfully so as it has very spotty support, especially with these new Thunderbolt hubs/adapters and smart monitors.

I’m glad Lunar works for you!