The exact same thing is happening to me. Used to get 8h - 7h 30min screen on time and now can barely reach 6h screen on time. The battery drain %s dont add up to 100% for me. (Using s21+)
i just found the culprit, force stop UWB aka Ultra Wide Band in application list. tap the right icon filter then tap show system apps, then find or just type UWB then you'll find 3 apps with UWB. turning it off stops the draining battery issue. 😩 i also turn off modes and routine, i thought it is the culprit since i never use it since day 1 including digital wellbeing. put them in restricted mode in battery.
I just saw a video of somebody doing a side to side comparisison between one ui 4.1 and one ui 5.0 on a similar device (s22 ultra i think) and i saw the battery percentage dropping faster one the device with one ui 5.0 so i looked it up and i found this conversation personnaly i did the update on my s21fe but i didn't see any difference yet, after all battery life was already bad on s21fe...
I am experiencing the same issue. I used to have at least 50% left at the end of the day. Now I am down to 10% at the end of the day. Actually, I'm down to 10% before the end of the day. I've always charged my phone during the night and have never had to charge it before bedtime. Now I have to charge it long before bedtime. Very frustrating.