I believe you need to rethink what the word 'imminently' means. The most aggressive timescale out there from the National Climate Assessment suggests a 4 foot rise during the next one hundred years. If that started today, its less than a half inch a year. Thats hardly imminent. Thats not even in your lifetime you see the 3 foot mark.
A century is imminent as it is, unless you think only in single-life timescales, and a two foot rise will be enough to make Miami economically unviable - as above, sewerage - and fresh water - will be severely impinged by a moderate rise.
That's 50 years, even with current models. If Miami is to survive, it needs new infrastructure, now - and even that will only hold for the short term. The only long term option would be a massive caisson building effort, building a huge concrete sheet wall around the city, buried deep into the strata, down to below the porous limestone it's built atop - at least 20 feet deep in most places. Even then, you'll have issues with sinkholes due to water being removed from the strata... in short, abandonment is where Miami will end up. Nothing else makes sense.
Sea level rise is accelerating beyond our most aggressive models currently, due to ice shelf collapse - Antarctic and Greenland ice shelves are vanishing much faster than anticipated, and will likely all be gone within the decade - expect new models over the next 18 months to predict some rather radical outcomes entirely within our lifetimes.
California is running out of water and has a few years left. Thats imminent. Florida sinking in 50, 100 or 200 years is not. A large percentage of tech folk are highly mobile and as such, florida sinking in even 20 years will not dissuade them from moving here as the vast majority of them are renters anyways. I dont doubt its something to think about and sealevel is definitely rising, I just was contradicting your answer that the one obvious answer is sea level rise. If you put it in percentages of why people move here, I doubt its even in a 5% range.
