We know we cannot trust service providers on the internet to take care of our identifying data. We cannot ensure they won't turn that data over to a corrupt government entity.
Therefore, we can not guarantee free speech on these platforms if we have a looming threat of being punished for the speech. Yes these are private entities, but they have also taken advantage of the boom in tech to effectively replace certain infrastructure. If we need smart phones and apps to interact with public services, we should apply the same constitutional rights to those platforms.
https://en.wikipedia.org/wiki/List_of_pseudonyms_used_in_the...