... as long as that speech isn’t (including, but not limited to) fighting words, sedition, incitement, obscenity, pornography, false statements of fact, counterfeit currency, commercial speech, speech owned by others, threats, slander, libel, defamation, and more.

... and also as long as the speaker isn’t being paid, isn’t speaking for the government, isn’t employing people, isn’t in prison, isn’t a regulator of the bar, the airwaves, the military, or immigration, and more.

https://en.wikipedia.org/wiki/United_States_free_speech_exce...

Some of those exceptions may be relevant to this particular article.