Kash, in reality, SergeyY's behavior and words in this thread shouldn't have any impact on the situation in the tournament you're running, and even less should they serve as justification for the decision you made.
We shouldn't bully the guy; he didn't do anything terrible.
And it doesn't matter that people like that are bullied in real life, in school, on Instagram, in the army... But we won't. We'll be good guys.