Military pilots are also professionals, and of the glider pilots how many of the best are trainers. Ag pilots are professionals, as are helicopter mustering pilots who are incredibly skilled. The majority of acrobatic pilots are also professional pilots. I’m not suggesting that great amateurs don’t exist just that a great amateur who has gone pro can often beat one that hasn’t.
I understand the sentiment, on one hand if I was rich I would be able to devote my time into constant improvement, but then maybe I wouldn’t have the same drive to succeed as having my livelihood dependent on the outcome. There is institutional knowledge gained by working in a research org that would be hard to replicate as an independent scientist.