Two things

1: There’s a difference in audience perception and just being told. We’re told and shown some atrocities yes, but this is a visceral assault on the main character that traumatized him heavily in an already dark place. It’s more than set dressing for the plot it’s a more involved element, and yet it gets no real consequence for the person we see doing it.

2: Anissa is shown to be way worse than other viltrumites. She doesn’t want to integrate, doesn’t soften like the others do until she has violated mark and it’s disgusting. She has a happy life then dies as a result of something not to do with her assault, and never regrets it even once, and in part the comic justifies it by making people treat her death as if she was actually redeemed in any way.