Current State of Sailboat Racing is Pretty Bad
I am not sure that you can make that broad generalization about drivers in dighies vs keel boats. I would say that some of the worst sailors that I have ever encountered have raced keelboats. If they had been racing dinghies they would not have made it to the course without a visit or two from the chase boat.
On the other hand, most of the best helmsmen that I have ever encountered were racing keel boats. Then again I never competed above a college level in dinghies and may unfairly base my opinion on that.