The analysis seems to focus on the number of companies, not by employee headcount, so I'm not sure this is indicative of the experience of living in Silicon Valley on average.
Realistically, today's business difference between Austin and Miami reminds me of what it can be like for a contestant on a TV game show who gets a big vacation win where they get to choose between Hawaii or the Bahamas for their prize.
So many people will consider them almost equivalent resorts without digging deep enough to fully realize in advance that Hawaii is a tropical paradise, and the Bahamas is a desert island.