The statement 'Tucker Carlson, reduced to doing infomercials for Elon.' refers to a conversation involving Tucker Carlson and a link to a website. The statement appears to be a critique or commentary on Tucker Carlson's activities, specifically suggesting that he is now engaged in promotional activities for Elon Musk. This does not constitute public discourse as it does not substantively engage with public issues, policies, or societal concerns. Instead, it focuses on the activities of a public figure in a promotional context.