You'll forgive me if I don't cry because you called me a name.
Freedom of speech means that you can get the good sort of speech along with the bad sort of speech. I'll give you an example.
Some years back, the American Nazi Party (or a branch thereof, I'm not quite sure), came to town to protest. They did their thing on statehouse grounds, in front of the Confederate flag, which was still flying on the north side of the statehouse at the time. (Careful readers will note that I have thus identified the state this occurs in as South Carolina.)
Now, I disagree with pretty much everything the American Nazi party stands for. But, inasmuch as I find them distasteful, and would not miss them if they were gone, they had the right to speak their mind. I forget what topic it was supposed to be on, but it very quickly descended into the racist claptrap that one expects from Nazis.
Likewise, I had the right to heckle them. Which I did. I'd like to think that I did so quite well, but lack of planning meant I didn't have a megaphone, so there was only so much volume I could project.
Now, if the Nazis had gone from speech to action, say, trying to thump me upside the head for heckling them, the cops (of which there were many present) would have gotten involved, because while free exercise of speech is protected, assault is not speech.
Freedom of speech does not mean that all of the speech you or I are exposed to is going to be speech we agree with. It might be. It might not be. We might not give a shit about what the speaker is saying, and are waiting for the announcement that the bar is now open.
But no privately owned venue or forum is required to give you a platform on which to speak. If I owned a comedy club, and I decided I didn't want a particular comedian to play at my club, it does not matter how often he trots out the idea of freedom of speech. I am not restricting his right to do his act anywhere else. Just at my club. It's privately owned. I can do that. (Note: I don't actually own a comedy club. It's just an example.)
Likewise, Twitter can choose to ban someone, or not ban them, under their terms of service. They can allow certain people to speak at their venue, or decide that they don't want them there any more and ban them. They are free to do so, because Twitter is not owned by the government.
Furthermore, as I have already said, freedom of speech does not make you immune from the consequences of said speech. If, to return to the comedy club example, a comedian at my club says all kinds of stupid/racist things while doing his act, and I decide I don't want him to perform at my club any more, I can ban him. I am, once again, not curtailing his freedom of speech. He is perfectly free to do that act anywhere that will allow him. But I have shown him the door.
And finally, you'll notice I disagreed with you, but didn't call for you to be banned.