I don't think that's a viable solution. Private companies can and do have a legitamate interest in restricting speech on their platforms depending on the circumstances. For example I may wish to set up a discussion forum on my companies website for my products but choose to ban discussion of anything that isn't directly related to my products or company. For example, US politics in general.

This is clearly a different situation than an outfit like twitter which I see as more akin to a publisher at this point. But even publishing companies have the ability to decide what they do and do not want to publish.

I think the biggest problem with Twitter is it has more or less established a kind of monopoly on the internet along with other large companies such as alphabet. But beyond that the viral nature by which content spreads and the lack of transparency do to the internet's anonymous nature or who is making the content and who how and why the algorithms are picking what is being chosen for spread are not at all well known.