May be I should add to the list of things that make a real pilot: the ability to learn from ANY other pilot.
Good point. Last summer, I watched the chief test pilot of a well-known French manufacturer being checked out on a Piper Cub by an instructor who was 25 years younger, and had just a fraction of his experience. However, the instructor knew how to fly Cubs, and both parties seemed to learn a lot from flying together.
As with most things in flying, attitude is what matters.
(Needless to say, the test pilot chappie did his Cub check out with a lot bounces than me...

)