Well, then I didn't misunderstand you. You're saying that in order for Captain to be not male, they'd need to be named "Captaina". Which implies that women (and other non-male individuals) cannot be referred to as "captain" because according to you, that's "masculine".
If anything, I'm apparently misunderstood, because I never labelled you as a sexist, I just questioned your less-than-logical logic.