There is a difference between how much you can hear and how much you can distinguish in what you can hear. The first decreases when you age (or when you are exposed to loud sounds). The last can be trained.
So I agree that it's likely that musicians have worse hearing (playing in a orchestra can/will give you ear damage) but they are trained to distinguish sounds.
So I agree that it's likely that musicians have worse hearing (playing in a orchestra can/will give you ear damage) but they are trained to distinguish sounds.