Husband's uncle proud he punched my MIL in the face and my husband said nothing

I never got to meet my MIL. My husband hasn't seen his mom since he was 11. She was extremely abusive and he got rescued by his uncle. His uncle is his dead dad's brother and my husband does call his uncle dad. His uncle has told this story a couple times on how he took my husband in. They had a feeling he was being abused and went to check up on him and when they saw him he was clearly malnourished and covered in bruises. He got into it with my husband's mom and he told her he was taking him. She said you aren't taking my son and he said he told her "You know. I don't hit women." Then punched her in the face and said "I will beat tf out of a bitch though. Then he took my husband and he never saw his mom again. He told this story at a BBQ and there is just something about a man being so proud he hit a woman that rubs me the wrong way. My husband clearly loves his uncle and I'm not saying what his mom did was right. But he was obviously stronger than her. He didn't HAVE to punch her. He just chose to. His uncle has said the state my husband was in made her black eye look like nothing. I asked my husband how he felt about his uncle hitting his own mom and he just said he honestly prefers not to think about her. He has moved on. Let a lot of hurt and anger go and she is nothing to him. I just kind of wish he would tell his uncle he was wrong for hitting her. But his uncle is his hero so he won't.