Hindsight only applies if its clear that it wasnt a great decision to make at the time. The entire argument is that we dont need him to fight when there is nothing to be gained by it at the end of a game against a bottom feeder. That is true regardless of reasonable outcome.
I would want them to stand up when its a truly dirty play, is egregious in some way, is against one of our star players, or could reasonably have a positively impact on the team (early in a game, in a playoff series, setting the tone for the next matchup against an important opponent, etc).
Saying that we cant decide at the time it happened that fighting Entwhistle with 3.5 minutes left in a 4-2 game against Chicago after a cleanish hit on Garland where Garland wasnt hurt was good or bad and we only know its bad in hindsight with the injury is something I disagree with. It was stupid because of a potential injury.