Having grown up in Sarasota and now living in Jacksonville as well as being a City Planner/GIS Analyst by trade, I would like to add some additional information to the mix.
A lot of the gentrification issues you both mention are valid but I believe other factors help contribute to it in Sarasota. Sarasota County has an urban growth boundary that mainly follows Interstate 75. Anyone driving down I-75 will see Big-Box Retail and other development on the Western side of the road and celery fields and cow pastures on the Eastern Side (there is some less intense development). "Subdivision Ready" land was available for development on the Western Side on the interstate until about 15 years ago. Around the same time a confluence of events occured:
*The City steped-up its work on its downtown plan (reconnecting the downtown core to the bayfront [which had been cut of by US-41], Turning Main Street from One-Way back to Two-Way, repaving Streets, etc..)
*The city redeveloped Island Park on the bayfront
*Available easily-redevelopable land on Siesta Key and Longboat Key for High-Rises became scarce.
*The City Hired Andres Duaney (of Seaside Fame) to work on its new Master Plan and Zoning Code (Around 1998-99)
*The Mass Brothers Closed and a very wise developer decided to turn it into a 20 Screen Movie Theater
*In town living as become a popular choice for many segments of the population
*Interest Rates Dropped and Development everywhere was red-hot.
* ETC...
Sarasota already had a nice core district as well as St. Armands and Osprey Village, thanks to Ringling, and Palmer, and others, but it literally exploded with growth once all of these factors collided (In the early 90s there was an article in a local magazie where someone said that you could light off a cannon after 5pm and not bother anyone).
As far as the gentrification issue is concerned I believe that, in part, there is literally no where for someone to move. In typical suburban growth patterns (at least in Florida) it seems that subdivisions lead to new subdivisions which lead to newer mega-planned super subdivisions and as people "upgrade" the whole population moves up or side-to-side. This for the most part has not happened in Sarasota. When you "run out" of land and the area remains desireable the result is what you see here. There is no path out for many people because the path is full of people.
I am absolutely glad that Sarasota is a progressive as it is with its planning. I think some of the city's and county's decisions 20 years ago are still seen in the development of downtown Sarasota today. I absolutely agree that this has had the unintended consequence of leading to very stratified areas and a complete decimation of affordable housing. Even so, I would say it is a better model to look at than the Suburban Sprawl of its Neighbors Bradenton and North Port which have other class and race issues to deal with as a result.
Whomever can help Sarasota with these issues is much smarter than myself, but I think the dynamics of the city are well worth studying.
I will say as a relatively new resident to JAX one thing that I believe the city needs to do is UN-engineer its streets. Everything here is a weird pseudo-connector/expressway/thoroughfare (Roosevelt Ave., The entire south bank of downtown, the Arlington Expressway, the Hart Bridge Connector Roads, MLK Expressway, etc...). Learning to drive here is a test of patience, some areas are truly maze like.
Very interesting to see this section. Thanks!
Sarasota 1973 - 1998
Gainesville 1993 - 1997
Celebration FL 1998
Atlanta 1998 - 2000
Naples FL 2000 - 2003
Tallahassee 2003 - 2004
Jacksonville 2004 - Present