Hi Alxndr
The brightness has returned to its behaviour of before the 3.A.0129 update of 5 August. As you will see from that very long thread, the 0129 sought to implement a wider range of brightness but failed to compensate for this in the adaptive brightness function. The result was, that for many users their phones would suddenly go almost black!
There is also a thread dedicated to the problem:
The version you’ve just updated to, 0132, simply returns to the previous values. A fresh attempt at improving brightness has been promised for a future update.
For my part, I also regret this return to a “minimum brightness” level that is far too high. I don’t use adaptive brightness much and was happy to adjust the level manually. Let’s hope they provide a better solution soon!