No it's not. It's a normative opinion. The opinions against it all have horrible repercussions and difficult questions to answer such as "who should be in charge of moderating or censoring?" and "how can we trust them?"
The first one is always "my party" and the latter answer is always "because they protect my interests, and your interests doesn't count."
Meanwhile most people agree that cursing, pornography or spam - and things otherwise clearly outside the bounds of the law - should be censored. And perhaps also obvious ad hominems. But that's not what we're discussing right now. Instead we're discussing whether a Democrat should have the right to speak on a Republican forum and spread Democrat opinions there. Today that is precluded because "it's a private enterprise."
Meanwhile if freedom of speech was better governed, you would have to defend against flaws and lies with facts and logic instead of censorship, or even moderation.
But then there isn't anything precluding private enterprises from making such a place. And I happen to think people would flock to such a place. There would certainly be a lot to win for the enterprise to have so many people there, but so far the only model that seems to have worked is one where all those masses are somehow guarded against each other in sub-forums, such as on Reddit or even on Facebook. But perhaps Musk can revolutionize Twitter? What do you think?