Another way to think about it: what if you looked out your window at night, and saw an unknown figure looking in? Would you rather it be a bear or a human (regardless of gender)? I think almost anyone (man or woman) would prefer the bear.

Context matters a lot. But generally speaking, unknown humans are one of the most dangerous creatures there are — especially if they are bigger than you (which is usually a good assumption when a hypothetical woman encounters a hypothetical man).