You never know the full story in these cases but it certainly sounds like she was mightily unpopular with the other FAs since so many reported her for doing everything from theft, to drinking on duty, to being physically unable to arm and disarm doors (I suspect they really mean secure the door following boarding - since that is the “physical” part).
I know this isn’t a popular position to take, but flight crew need to be physically fit to a minimally acceptable degree for safety reasons, and I have seen several 70 plus FAs who clearly had difficulty pushing the drinks cart down the aisle. We need to be sensible about this.