But do you think it's likely to be significantly wrong simply because a number of countries have outlawed denying it altogether? As you surely know, it is not a legally punishable offense in America to deny the Holocaust or anything else. Are you asking why it is so in places like Germany and Austria? I'd guess for the same reason the Nazi party itself and paraphernalia advocating for the Nazi party are illegal: they don't want anything like a Nazi takeover to ever happen again. It's an extraordinary measure, sure, but there are, in my opinion, historically sound reasons for its existence in those countries.
What "historically" sound reason is that? I thought punishment for speaking was put behind in the Dark Ages. It's illegal there because that's where the truth is. Voltaire would heartily disagree with you.