Ya I think the problem is that forums bring out people who say some truly terrible things, and there isn't really much you can do about it. They say stuff to men too - but it's more death threats than sexist, and they say racist things to (or about) blacks and jews, muslims, latinos, and the chinese too.
The perils of anonymity I suppose.
It's not like it isn't a valid concern that people are out saying these things, but jews and blacks essentially face the same problem: if you go and look at a few hundred or a few thousand internet comments on any post there will be a couple of things that are basically just crazy people rambling. Unfortunately you don't know when random crazy people rambling on forums are actually a threat (if ever), and that they exist and want to say those things at all is a bit of an existential threat to your general day to day existence.
There isn't really an obvious prescription. You can educate people all you want about not saying offensive things, but a small handful of people will continue to say offensive things because they're trying to be offensive. And the anonymity of the internet lets you say both unpopular things which are valid, and unpopular things which are just nonsense.