Of course. and it works fine when plugged in. The toggle works switching the modes. Just as it works when i have battery over 75%.
somehow below 75% unplugged - its stuck in Dark mode. and switching on/off doesnt do anything. I can use the toggle, its not like its greyed out. but it remains in Dark mode always.

I have the exact same problem with my Mi 10t it switches between the light and dark mode normally when charging, but as soon as i unplug it, it goes dark mode-_-
I would say it happened to me like 2 weeks ago