Wiki - The paradox of tolerance states that if a society is tolerant without limit, its ability to be tolerant is eventually ceased or destroyed by the intolerant. Karl Popper described it as the seemingly self-contradictory idea that in order to maintain a tolerant society, the society must retain the right to be intolerant of intolerance.
I disagree. He asked a question that gets to the heart of the question, given that the definition of what is "harmful" has changed over the years and will continue to change into the future; does OP support the censorship of the things it would have censored and the things it may censor in the future? It's a valid question and it core to the disagreement.
If OP doesn't care about the dangers of censorship that's fine, but they shouldn't act like you can allow censorship without the problems it has historically and will in the future cause.
The disagreement is that censorship can be good at all. Censorship, even with the best of intentions has always been a net negative for a society. And there's no standard for censorship that can withstand simple historical analysis rigor. Censorship is always a powerful group limiting the speech of the populace.