I think the question of whether to intervene has to extend beyond what happens right in front of us. Part of the problem we face with many of these social issues today is that most straight, white, cis-gendered men actually can go their entire lives without witnessing a distressing amount of racism, sexism, or homophobia. That audio recording of Harvey Weinstein and the young model was really disturbing to me. I've never in my life heard a man talk to a woman like that. I mean, sure, I could say "if I'd been there..." but it was no accident that I wasn't, predators like that don't want anyone else around, so the real question is, "What can I do about these things that I'm not there to interrupt as they happen?."
I keep going back-and-forth on whether members of any group have an obligation to stand up against their group's misbehavior, even if they, individually, don't perpetrate or perpetuate the misdeeds. (I don't just mean right now, I've been wavering on where to stand on this topic for decades.) This applies to a bewildering array of issues. For myself, I've kind of adopted a policy of sticking my nose in from time to time, but not demanding that others do the same. That is, I won't tell a member of another group to "come collect your people", even if I think that I would if I were in their shoes. It's a little self-serving, but I haven't come up with a better guiding principle yet. In my defense, I have done things to help groups of people other than mine. I'm not all talk and no action. But still, part of my privilege is that I'm kind of free to pick & choose my battles. I mean, yes, choosing your battles is how you preserve your sanity, but women and people of color and LGBTQ people can't always choose to take a break from those concerns (or not easily, at any rate). So, yeah, back-and-forth I go. I can't even say "like a metronome" 'cause I'm not even predictable about it. A black woman on a radio show was talking about the alt-right and neo-nazis and how White folk "need to come collect [our] people", and I was like, hey, those aren't my people, I have nothing to do with those tools. I know, that's very convenient (for me). If I wasn't just talking back to the radio, if she'd been in the room with me, I'd have probably kept my mouth shut, because I know that's not a good answer. I'd like a better answer, but I haven't found one.