Looks like you’re out of the loop on this. No OS has the ability to control the real brightness of the monitor out of the box.

At best it could dim the brightness through a software overlay, but neither Windows nor Linux implement DDC/CI brightness control by default.

You have to use a third party app like:

- TwinkleTray [0] on Windows

- Lunar [1] on macOS (or MonitorControl [2] if you want a free, but less automated solution)

- ddcutil [3] on Linux

[0] https://twinkletray.com

[1] https://lunar.fyi/

[2] https://monitorcontrol.app/

[3] https://www.ddcutil.com

EDIT: sorry for answering, I should have taken a look at your comment history before to see that BS comments like this are your thing