So the overall lesson of this thread is: Don't stand up for teammates because the game has changed and it will have zero effect.
Nobody has said don't stand up for teammates.
This isn't a one-size-fits-all situation. Player suffers dirty hit, teammate retaliates, honor served, team bonds. Black-and-white happens sometimes, but in a real, messy world, things are often gray.
Take the Cooke-on-Savard hit, which no Bruin other than Ryder (who wouldn't fight if his own life depended on it) saw. But they were still blasted to kingdom come for not responding. There was another time when Ference came to Recchi's aid when Recchi suffered a head shot, pounding the snot out of his attacker (I forget who it was). Only problem was, Recchi wasn't hit in the head. It was a clean hit. Whoops. (And Ference, after seeing the replay post game, apologized.)
Sometimes nobody sees the hit. Sometimes a player is so badly injured that getting him help is the top priority, not fighting his attacker. Sometimes a dirty hit looks clean, or vice versa. Sometimes the officials step in. Sometimes the offender won't engage. Sometimes retaliation is delayed. And sometimes, winning the game is paramount.
As I said, I can't judge. I'm not on the ice or in the locker room. Pro hockey games are exhausting, emotional, difficult affairs, and it's easy to be a warrior and to say what others should do from the comfort of the couch.