An interesting counterpoint - I was chatting to an older male friend about the problem of domestic violence. He said that the problem with the idea that "men should solve the problem by calling out other men" is that actually abusive men know that they shouldn't bring up their bad behaviour around their male friends who don't also agree with it.
So a "good guy" is unlikely to actually know if his friend is abusive or not because the abusive friend won't share that if he knows he's going to be judged.
He shared an example of a couple that was friends with him and his wife for several years. According to appearances everything was fine. Later after the friends moved away did he find out that the man was abusive and that his wife left him because of DV.
If my friend had known his friend was abusive he would absolutely have said something and he and his wife would have helped the victim get away.
But if you're known to be a "good guy", "bad guys" aren't going to share things with you that they would with other bad guys.
And bad guys aren't going to stop each other.
Now if a woman tells a good guy "your friend hit me, your friend was abusive to me, your friend raped me" then the good guy absolutely should take action. If they don't, they are complicit.
For example my dad knows his brother raped his sister. And yet he still associates with his brother. That's being complicit and that kind of behaviour needs to change to make society.
But the problem with abuse is a lot of it is so secretive.
So I can see a situation where a lot of guys don't actually have anyone in their friend circle that they can see is abusive or sexist. Because the ones that are are hiding it. So they ask - why is it my job to stop bad guys who I don't even know and associate with? And how are they supposed to do it?
And that's a fair question with no easy answer.