Sounds like he made a few claims: 1) "An introverted woman will still get approached by men", 2) "Introverted men, on the other hand, often just don't pursue women, especially if they have low testosterone (or sex drive) as the OP probably does", 3) "In most cultures men are expected to do the initial approach", 4) "introverted men are often very bad at reading women's signals", 5) "women just don't need to signal that much to get results".

1, 3 and 5 feel like super common sense to me, were you asking for sources on that? I'm asking mostly because I wonder whether my intuition is completely off when it comes to these things, or if there are people who live in completely different realities where women are expected to make the first step, more women approach men than the opposite and men really don't need to signal interest because they get so many offers.