I don’t know about south Florida but north east florida beaches were closed sometime ago. In my little place of the planet where beach going seems to be few generally inasmuch as there is little nearby parking, we have been closed for almost two weeks (Nassau County). Out of 80K residents in the county we have 8 cases, 2 hospitalized. Past rt 95 west, it is mostly a rural county.
Unless you make physical contact with an infected person, it is almost impossible to pick up the virus at the beach.
And, most suck people will not be going to the beach.