Finally DDC/CI works on my Mac Mini M1 2020 OSX 12.6.
All I did was replace the HDMI-to-HDMI with USB C-to-HDMI cable .
(No adapter was tested. I have Acer 4k 60hz monitor with HDMI and DP ports, so not sure about the functionality with other monitors.)
Now, I can control external monitor from mac osx.
Use: https://github.com/MonitorControl/MonitorControl