Free speech is not forcing others to listen to what you want to tell them. They have the right to not listen to you. Imagine a situation IRL, you are in a public place and discuss with your friends about a topic, let's say a new movie you've just watched and someone you don't know joins in and start calling names, saying that movie sucks...you ignore them for a while, then walk away and they follow you and keep yelling at you. The exception is that IRL, people don't do that (unless they are mentally ill) or they'd get punched in the face.