Now, there are separate issues here - the limit of banking for "bad actors" (terrorists, hate speech, democracy activists...).
That is mostly happening through the proper channels, that is the police and the judicial system do the policing and the legislative system makes the rules.
That in itself isn't a safeguard against abuse - but the other aspect is the privatization of utilities, and self-moderation that these companies do.
In between is the credit rating system, which allows for pretty arbitrarily denying banking services to individuals.
Still, if you are paid in a regulated currency, you still have an option to use cash. An access to legal tender.
With something like Libra, a private corporation, with a horrible track record wrt complaints/customer service can vanish your money because a friend shared a picture on your "wall", or some other entirely arbitrary thing that leads to account suspension.
You don't have to go out of your way to purchase fertilizer, diesel and nails - you could do a million different completely innocent things and still be locked out of your money - with no real recourse - including a viable legal recourse.