I am going to guess that there is a simple answer to this. One which isn’t ridiculous. But I did stumble across this a moment ago and was surprised.
Twitter has a setting which censors “offensive material,” porn, murder scenes, other graphic content, and I am actually OK with this. Twitter is a private company and can censor what it wants (though if it really censored content it would affect the value of the company) and one can opt out of this censorship anyway.