I think you're mistaking the feeling of guilt with the state of being guilty of something. The person you're responding to isn't claiming that SBF demonstrated

I think you're mistaking the feeling of guilt with the state of being guilty of something. The person you're responding to isn't claiming that SBF demonstrated remorse at his actions, he is claiming that SBF admitted to the crimes he's been accused of. Whether or not he feels remorse for those actions is a separate concern. But yeah, he's guilty.