Earlier quoted context omitted.
> The entire western world bans holocaust denial, and it hasn't led to a chilling effect on other expressions. Debatable. Banning holocaust denial is one of the greatest travesties in Western free speech. You just gave anti-Semites one more reason to believe there’s a global Jewish conspiracy going on and another recruitment tool.
You'll have to explain why it's such a great travesty because it's not obvious.
Because it hides the truth. Perhaps someone will discover people you wouldn't expect involved doing things we wouldn't expect which may cause some aspects from being denied to cease to be true. Silencing one groups end up silencing another.
Why don't we have a law banning denial of other genocides like the Armenian genocide. There should be an equal concern for all genocides being denied.