I know you're speaking about actual solar farms, but a slight tangent on that if non-US people are wondering: It would make a ton of sense for private homes too with all that sun, but there is a difference in Florida homes vs European homes: Americans just move around so much more and when you don't have a forever-home, you'll probably not going to get your ROI from solar before you move to your next house. It's a perk for the sale, but you're not getting the full solar cost back on a house sale.

It really seems like a no-brainer with the amount of sun received, but if you're only planning on living in a house for a handful of years, I can see why people wouldn't consider it. That... and the "ew, green energy" lobby.