It's tempting to blame this on female dominated spaces, but well, I've seen it happen other places. Although certainly it seems to me female shaped people are asked to be nice, to not make waves, to grin and bear it at higher rates than others.
But let's talk about what we mean by nice. Because if someone does something harmful and I speak out, certainly I could do so in a way that was not nice, but my speaking out about harm caused to me or others is not mean. And saying, hey, don't be mean isn't solving the conflict, it's shoving it in a drawer. More importantly the implicit message is, you don't care that I or others were harmed. You care more about maintaining the illusion of nice. And don't be fooled, letting harm continue is absolutely not creating a nice place. Except you really like that place. And maybe it's the only place that has this one dish that I really like. And every time we meet for lunch, or almost all my friends want to meet, they want to meet there. And I hate it, because I never know if I'll get what I ordered or I won't. And sometimes I just don't eat because I'm too tired to keep arguing with them.
But then I discover someone else who hates going there. And I ask them and discover that they have the same issue I do. And then we discover, there's a bunch of us. So, we go to the restaurant and tell them we want to be treated fairly. We want to get orders that are correct. And the restaurant starts doing interviews with the local news that a few mean people, who probably hate restaurants anyway, are trying to kill their business and if these people get what they want, they'll have to fire all the nice employees at their restaurant.