I mean it's both as you noted. When I did social media more it would be "fun" to go through uninvited messages to laugh and sneer at them with friends (this sounds mean, but you haven't seen the messages I'm talking about). I always had to add anyone because otherwise there were like 800 friend requests from complete strangers and I don't understand that.
Being out is dangerous too.
Online creeps seem less harmful. I've had some unpleasantries with people I've met online, but the ones that were dangerous seemed to be random individuals.
My sister was once walking at night and had a man come up behind her and say "Don't worry, I'm not Black(like that mattered)." He walked and talked with her for a moment(she was walking home and had nowhere to retreat to), presented a knife, robbed her, and then told her she was really cute.
That one was awful on so many levels...
We just have a crappy culture where creep behavior isn't negatively reinforced by peoples' friends. If people would check their bros (or their girlfriends, or their persons) on the behavior more maybe it would be a little better.
I did have one instance where my friend's husband diverted his cousin from pestering me. We were all at a bar, and his cousin kept hitting on me. Jokingly at first. I was seeing someone, wasn't interested, and said so. As time went on, he started getting more persistent, and mildly aggressive. My friend's husband put his arm around me, told his cousin that we'd been screwing around on the side, and he was to leave me alone. He was drunk enough that it worked... (and I think my friend's husband recognized that). I was always very appreciative at how he de-escalated that, and in such a humorous way.