I was just looking at some of those towns on Google Earth.
St Marks is 4 ft above sea level and right on a river that will surely back up for miles. Panacea is 5 ft above sea level.
St Marks is very flood prone (river) anyway, and the folks there surely knew to get out. Hurricane Dennis did huge damage there in 2005, and wiped out Poseys Oyster Bar (great eats!), which had been there since the 1920s.
Michael did damage to all those places in 2018. Now it’s Idalia. So much for the “No Hurricane Coast” lately.