People don't make the same decisions as emotional teenagers than as logical adults, people don't make the same decisions around family in private than they do around outside authority figures in public, and people don't make the same decisions when they have years to vent and build up an issue as they do around one-time events that happen in the spur of the moment. Plus he didn't "brag" about beating up his father, he told it as a tramatic story of his childhood.
Are you suggesting that he should have crashed out and beat up the guy at the party? Because that more likely ends with him in jail than with the other guy in jail. Or are you just suggesting that he should have reported it? Because yeah, he should have, but the vast majority of people who are sexually assaulted by authority figures in their profession don't report, and I don't understand the obsession with victim-blaming that I see on these pages, unless the goal is to get every victim to shut up and ensure that nothing ever sees the light of day.
Wait, I didn't see this at first, your entire argument is literally "don't expose abusers".