I agree with you on restraints on natural monopolies. That should come in the form of limiting their anti-competitive behavior and probably also harvesting user data unconsentually for profit.
But regarding limiting these companies from being able to decide which speech they don't want to host: I don't think you've thought this out fully.
What speech should they be forced to host? Art? Disinformation? Propaganda? Porn? Spam? Terrorism? For illegal speech: Whose laws should they be forced to obey?
With respect, no speech should be illegal, regardless of how absurd, abhorrent, or inaccurate the speech is to anyone. Free speech is fundamental to a truly free society, full stop.
You disagree with your own statement and you don't even know it!
"No speech should be illegal" - should I be able to threaten people then? That's speech. Should I be able to detail my plans for how I'm going to commit a crime? That's speech.
Should I be able to scream at the top of my lungs in a public space?
Should I be able to use a loudspeaker to broadcast my voice (or an advertisement) to drown out all other sound in a public space?
It sounds nice what you're saying, but it's not what you actually believe, so I kindly ask you to argue less in bad faith.
You're right. We should make exceptions to free speech only for recklessly, knowingly, or intentionally:
-making unreasonable noise and continuing to do so after being asked to stop
-disrupting a lawful assembly of persons
-speech made for the principal purpose of creating panic
-if the speaker intends to incite a violation of the law that is both imminent and likely.
My solution to the original problem would be to make it technologically unfeasible to solve. The architecture of the communication platform should be constrained in such a way that operators & owners are unable to make choices about which speech to include. This is because nobody is equipped to solve this problem, and nobody should be forced to do anything to try and solve it.
Disinformation, and propaganda are just specific types of protected free speech. I disagree with socialism, but communist propaganda is protected speech which should be allowed. Disinformation can be dangerous too, I understand that. But i'm not willing to allow Google or my government to make a decision on what is disinformation.
As for everything else. You should clearly follow the laws of the country you are doing business in.
But regarding limiting these companies from being able to decide which speech they don't want to host: I don't think you've thought this out fully.
What speech should they be forced to host? Art? Disinformation? Propaganda? Porn? Spam? Terrorism? For illegal speech: Whose laws should they be forced to obey?