I’ve always thought that courses in Florida were rated easier than they played. In Florida if you hit your drive right or left you’re in water taking a drop and hoping to make bogie. In western NY you hit the same tee shot and you’re in the trees but have a good chance to save par or even once in a while hit a really great shot and make birdie.
You're likely considering how you play it EVERY round, while your counting scores only come from your best 8 of 20 rounds. On your best 8 of 20 you're not as likely to hit it in the water, etc.
If anything, I've seen Florida courses I think are slightly over-rated… because they'll assign a "3" for trees when there is like two palm trees on the entire hole. A 3 at some northeastern courses is… a bunch of pine trees all down the left side and a few oaks on the right.
(Slightly exaggerated — that sounds like a 4 or a 5 to me, ha ha.)
Your "feel" is a common one, though, and maybe they are slightly under-rated. But as a golfer you generally consider all of your rounds, not the best ones that count toward your index (which is all the course rating is really about - your handicap index).