For what it's worth, I've seen just as many men as women claim that they are "fast learners" and whine about the dancing deficiencies of the opposite sex, and how the "bad" leader/follower is holding him/her back. And I've seen just as many women as men "teach" on the social floor.
From my perspective, it's a stage that dancers go through when they get past the point of being absolute newcomer beginners but before they get to the level that they realize that dancing is about more than just memorizing steps.
If the people you are commenting on are somewhere in beginner/pre-bronze syllabus to mid-bronze syllabus level - well, just be patient. Depending on the situation, well, a little comment (said with a BIG smile) something to the effect of "hmm, well, funny thing - but I heard "X/Y" complain about just the opposite when it comes to "Y/X" - isn't that interesting...". Or, if they get really, really annoying about it: "Hmm, well, I've heard you say that you're a quick learner, so surely you're good enough to cover the mistakes that your partner is making - aren't you?"
(Note: that tactic might not make you popular.)
Good luck.