I have been shooting a bow for 60 years, I have never had a bow string break on a strung bow (I make my own strings), never had one cut by an invisible spirit but I have straightened the limbs on a bunch of bows that people torqued the limb (step through method I suspect) while stringing and unstringing. I have also heard of people putting their eye out when a bow slipped out of their hand with the push-pull stringing method. I have cut a string or two with a broadhead while bow hunting, the bow wasn't damaged, it was a Bighorn which were really well made.
I don't see a thing wrong with unstringing a bow if that is your preference, just use a bow stringer to be on the safe side.
I am a selfbow guy now and wouldn't think of leaving one of my osage bows strung if not in use.
Black Widow once stated that more damage was done to their bows stringing and unstringing them than anything else.