from Android 14 update until now having same problem,
- in total dark, auto not set less than 17%
- if i slide to %0, after power off/on: 0% is some sec and return to 17%
now i found & try reset BL data:
- Settings/Apps/All apps
- in upper-right 3dot select “Show system”
- find “Device Health Services” app
- Storage & cache/Clear storage/Reset adaptive brightness
and in low&dark go auto to 0%, after power off/on keep on 0%,
on high light go to 100%… bso far only tested in indoor-artificial lighting
Edit: auto to 0% work with and without DC dimming