Neither dogpiling nor shaming someone stops them from speaking. Those are responses to speech, and they are speech themselves. Some people seem to think "free speech" means that people have to give them a platform, and listen and agree to their ideas. That's not the case. No one's stopping you from speaking by refusing you a platform, or disagreeing with you in number, or saying you're a bad person for saying what you said.
You can speak, but that creates no obligation in anyone to listen, take you seriously, or allow you to speak without response.