https://wccftech.com/macos-monterey-12-3-beta-2-fixes-bluetooth-battery-drain-issue/

macOS Monterey 12.3 beta fixes an issue with MacBook users that was causing severe battery drain overnight.

With the release of macOS 12.2 Monterey, Apple introduced a weird and annoying bug for users who own a MacBook - any MacBook at all. If you put the device to sleep overnight, it just wouldn't properly, because it was being constantly woken up by Bluetooth devices that were trying to connect to it, such as a Magic Mouse or even a pair of headphones. So, at the end of the day, or night, you would be left with an almost dead notebook even if it was on sleep.