Google and Facebook have natural monopolies. The answer isn't to break them up (which will just restart the cycle) but to place them under public ownership. This would also enforce first amendment rights on both platforms and disallow the legal side-step the government has been using to pressure them into censoring people.
Public ownership isn't really necessary and comes with its own downsides. All that's needed is to apply the first amendment to these companies, which can be done either through legislation or through the courts applying Marsh-like reasoning about freedom of speech in privately owned public accomodations.
It could still happen, but I am doubtful. The public option appeals to me because it also erases all the advertising and spying incentives these guys have.