Compelled Hosting Isn't Rendered Unconstitutional by the Host's Being a Speaking Organization
Another excerpt from the First Amendment section of my Social Media as Common Carriers? article (see also this thread); recall that the key First Amendment arguments are in this post, which relies on the PruneYard, Turner, and Rumsfeld precedents, and in this one, which explains why Miami Herald, Hurley, and the various other "common theme" precedents don't apply.
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The precedents I discuss show that the law may require certain private property owners to allow public access even when they are themselves in the speech business:
- Cable systems, the Court made clear, are "entitled to the protection of the speech and press provisions of the First Amendment," and indeed sometimes supply "original programming" of their own.
- Universities of course engage in massive amounts of their own speech (including by curating others' speech, for instance when organizing symposia) on their property.
- Even shopping malls usually display and distribute their own speech on their property.
Yet all three can still be required to host others' speech.
Likewise for social media platforms. They indubitably speak themselves, for instance when they choose to recommend particular material to readers (more on that at p. 71). The government can't demand that they include sites they dislike within those recommendations. And, as with Rumsfeld, the platforms retain the right to "voice their disapproval of [users'] message," for instance by posting fact-checks or warnings, if they wish. But this speech by the platforms, like the speech engaged in by universities, doesn't give them the First Amendment right to stop hosting speakers they dislike.
 512 U.S. at 636 (cleaned up).
 547 U.S. at 69-70; id. at 65.
 One of the reasons that NetChoice, LLC v. Moody struck down the Florida social media rules was that they, "unlike the state actions in FAIR and PruneYard, explicitly forbid social media platforms from appending their own statements to posts by some users." No. 4:21CV220-RH-MAF, 2021 WL 2690876, *9 (N.D. Fla. June 30, 2021).