router99
I read through the automatic brightness code for AOSP a long time ago. I don't remember specifics so I'm going off memory here, but the service resets some (for lack of a better word) personalization stuff when it detects the phone moving from one kind of environment to another. If you move from dark to very bright gradually, then it should keep your preferred brightness settings +/- its defaults for that same environment on a curve.
If you built your own version of GrapheneOS, you could hard code some values for the curve, making it max out the brightness at a certain level, but that's the only way I know of, unfortunately. The auto brightness feature in AOSP is very basic