Organized groups backed by various governments directly or indirectly will pose as extremists, flooding the platform with bots to post increasingly obscene content while pretending to be organic users. The intention of such groups is to get the platform banned so that users are kept on platforms they control.

This is all rather easily averted and solved if someone actually cared, but no one cares.

The problem could be solved by a sort of KYC (know your customer) rule that then is used to silo the platform on a per country basis.

Imagine a reddit that consisted ONLY of your countrymen's genuine comments, without any bots or alt accounts, without any foreign state actors repeatedly pumping divisive stuff to the top.

Further, imagine a sort of certificate authority for identity per the KYC systen.

Americans using this free speech platform could all be anonymous to eachother, but still visible to the feds if they used the platform to post illegal content. There would then be no need or reason to censor speech. People could talk of taboo subjects freely and openly behind their usernames without having foreign ragebots in a Russian trollfarm tur ing it into a flamewar.

You know, maybe Trump's team that recieved huge investment would build such a thing. Who knows.