See also my prior post about this.
People have also complained on Reddit and even filed a bug report. I knew people were not going to be that happy and I will try to see if it is somehow possible to decouple manual and automatic brightness treatment. In other words, if manual brightness is used, then allow the old minimum value of 1 - but for automatic brightness restrict Google’s weird algorithm to not push display brightness below 10.
If that fails I suppose we can put it up to vote whether we just revert the last change.