I've stood up for someone in that kind of conversation. Our boss was yelling at a colleague in an inappropriate way. I interrupted to defend the guy. Our boss said, "If you don't feel like you need to be here, you should leave the room." I left the room. No adverse consequences to my job, as far as I can tell.
I suppose I could have stayed, but I also figured my colleague could stand up for himself. He's not a pushover.
Not saying it's still not the right thing to do, just, you should put yourselves in their shoes. Probably that entire room could have told the guy in unison "that wasn't cool" and they would have all been instantly fired, so, not sure what that's gonna do for anyone...