People disagree about the definitions of crimes involving publication. For example, almost everyone is against the freedom to disseminate child porn under the excuse of "free speech." Then, some people are against free dissemination of ISIS propaganda, especially when it contains concrete calls for violence. Then again, disseminating Neonazi propaganda with similar calls for violence is not more legal than ISIS propaganda in most countries. Revenge porn and sites dedicated to slander and libel are prohibited in most jurisdictions, too.
The US has lax application of laws against right-wing calls for violence but is well-known to enforce against free speech if other groups like Islamists are involved. In the past, communists and civil rights advocates were also not too welcome. Other countries apply laws more stringently. In various modern and democratic countries content hosted by Stormfront is simply illegal and various posters on their forums commit crimes. Their servers would be raided and shut down by the police if they were under the country's jurisdiction. The US was never governed or occupied by full-blown Nazis, so it is only natural that people tend to be more liberal about these matters there, but that's more of a historical coincidence than an argument.