If you can create an impression that a lot of people believe in the thing you're arguing for, you can create a cult and influence real world events, such as wit

If you can create an impression that a lot of people believe in the thing you're arguing for, you can create a cult and influence real world events, such as with qanon. You can also cause enough psychic damage to eventually activate someone mentally unstable into doing something like bringing a gun to a pizza shop and threatening to kill people there. Idk if polite conversation has a purpose on the internet, but seeding the internet with information can certainly serve a purpose. Idk if it's served good purposes yet. Specifically in terms of textual content and arguing. Images and video obviously had impact in revolutions.