It's booming in the sense that wealthy people are buying up property.
That isn't the same as being a new hub for a lot of business creation and frankly haven't seen a lot of evidence established companies are eager to make it into a new hub or that there's a bunch of growing startups there with real traction.
The Chicago to Miami move is primarily an income tax avoidance scheme common in the HFT industry within Illinois, especially after the state instituted a 5% income tax after the IL budget crisis in 2017-18.