I have noticed the same issue. Surface Pro 11 X Plus and Signature Surface Pro keyboard (no bluetooth, it's the one I bought for my Pro 8 a few years ago).
The problem occurs when the device powers off (shutdown or hibernate or automatic hibernate while sleeping due to maximum battery drain being reached)
After it powers on, the keyboard is not detected.
Don't worry about wearing it out by pulling it off and re-attaching, the whole point of this design is to allow you to do that frequently during the day.
But this does need a firmware or driver update from Microsoft. Could be firmware in the keyboard or a UEFI update or driver in windows or even all three.
This is 100% a bug that they need to fix, don't waste your time reinstaling windows or anything like that. Just use sleep overnight. If Surface history is an indicator there will be an update before Christmas that just says it 'improves stability' and it will start behaving.