Yup this is coming. The "slippery slope" is real and recent actions confirm it. This is scary and these actions are unprecedented. The USA has never seen such restrictions on free speech in its history
What is unprecedented is giving these loonies a huge platform that helps them find like-minded loonies to organize while keeping them in an information bubble that shields them from corrections.
It would be prohibitively expensive to find enough like-minded loonies to organize a coup using telemarketing or physical mail marketing, and the act of doing so would annoy enough people that you would get shut down anyway.
Deplatforming dangerous loonies on Facebook and Twitter is not a new thing. It already happened with ISIS.