It is important to distinguish between what the coach is getting paid per hour and how much he is charging per person per hour. I think a lot of the replies aren’t being clear about which is being discussed.
A coach running a pool load of people for $63/hr seems very reasonable to me.
A coach charging $63/hr per person better be amazing.
I can’t imagine a coach writing up a plan, driving to the pool, organizing the training, providing feedback, taking notes, and going home for $20 unless he is just doing it to get out of the house.