Yeah, nah... not exactly. The right to free speech in the first amendment is quite different to people suddenly expecting a private tech company to have never had any rules or preferences about what speech is allowed on their free platform.
As previously mentioned, LU also has rules about what should and should not be posted here, and tools to ensure those preferences are upheld. All perfectly reasonable.
Twitter is a business, would get lobbied by all sorts of people from all sorts of angles to do all sorts of things, but makes/made its own choices to do what it wants with regards to freedom of expression on its platform. Can't see a legal case being built by anyone against Twitter for their suspecnsions or visibility filtering being a breach of the first amendment of the US constitition

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