lol.
it's not the size of the storm; it's the angle of approach. if this same size storm was moving due west and headed straight for miami, you'd evacuate the endangered areas of monroe, dade, broward, palm beach counties.... maybe collier, martin, and st. lucie counties.
the issue is that given the uncertainty of the track and the logistics of moving so many people, you have to evacuate before that track is nailed down. this thing could still hit the keys, the southwest florida coast, or just about anywhere along the east coast of florida (and places north).
it's about the number of people in the cone of uncertainty moreso than the size of the storm.