When the car has been roasting in the Sun, the interior can be 140° ... that includes a fair amount of mass involved with plastic and upholstery. True for any car sitting in the Sun. I find that with the A/C running wide open, minimum temp and Recirculate it takes maybe 6-7 minutes to get things nice and cool inside. If it's really toasty, I'll open the windows and the roof for 20-30 seconds as I get into motion just to evacuate some hot air. But, all those hot surfaces still have to be cooled. True for any car. I find my smart cools down as fast or faster than other cars I've owned. And, after those first few minutes I end up cutting down on at least the blower speed.
If it isn't nice and cool after 6-7 minutes max, you may have a problem to have checked out. Don't forget to use recirculate, especially for starters.