No, it is a limit on free speech but it is one of several that various governments (and cultures as a whole) throughout the world have upheld fairly consistently. Free speech is more or less an unachievable platonic ideal that we aspire to. Success varies, as do the compromises made along the way.

Speaking more generally, don't let your ideals bias your judgment. Just because you support policy X and also view ideal Y as good that doesn't mean that X isn't detrimental to Y. It's important to be objective about these things.