I think the point is that people who say (shout) "Not All Men" are usually frustratingly insensitive and the thought of throwing them into a snake pit is fun. We know it's not all men, we aren't stupid, but we also know that even 1% would be one percent too many to feel safe alone with a stranger (and, unfortunately, statistics suggest harassment is certainly more than 1%!).
Well, most people aren't that stupid. There's a few who are, but I don't think they'd be posting here, lol.
That said, reading the comments, I get why some are offended even though being male is the privileged class in this comparison (after all, I don't feel afraid to walk home at 1am). Men are fucked by the patriarchy, told to repress their emotions, degrade people who break from masculinity, and so forth. But instead of saying "you're being sexist against men," please try to think of the systemic problems that led to that X% of assholes who make it unsafe for a woman (or POC, LGBTQ, etc) to walk alone on a street in America.