It won’t happen. It is incompatible with the first amendment. Thank god we baked that shit in instead of just passing a law to that effect.
If the USG were to order Twitter to take down X person's tweets because it hurt someone's feelers, that would be a clear violation of the first amendment.
Additionally we have a strong legal precedent of not permitting "compelled speech". Plainly put, they can't force you to label your own Facebook posts with your opponents claims as well.
I am totally on your side that these few companies are in far too much control. But they aren't the USG, or compelled to block/force-speech on their behalf.