You read San Francisco is the center of the universe because there really is a network effect for software development. Companies looking for a bigger pool of talent to draw from relocate to the area, post jobs, and bring in yet more developers. On your South Florida island can you find someone with ten years of Cobol or five years programming 12F675s? If I started a company there, how many people could I hire that have solid experience in Scala? Not "I played around with it after work" experience, but real experience?
My point isn't that San Francisco is worse than this or that, but that every day I read that it is the center of the universe, and recruiters used to tell me "but you _have_ to be here, this is the place to _be_" which is terribly unconvincing for persons of my particular persuasion, nevermind that I don't care for wading through bums and traffic.
TL;DR it's a huge universe, and you don't have to put up with California to develop software in it.