They will pay it. They wont have a choice.
A state can only make laws within their jurisdiction which is their state. My state can't make a law that all ballots in Georgia have to be hand counted because we have no jurisdiction in Georgia.
If Twitter and Facebook were based in Florida, then they could write such laws. I don't know where they are actually at, I'm guessing in Silicon Valley somewhere, but a Florida legislature cannot write laws that pertain to a company in Silicon Valley. No court could enforce those laws because of jurisdiction.