@DW2 I would disagree with the assessment that women think they will still be fertile into their 60s. Rather, the delusion is that they think the can just transition from a single woman "living in the moment" to finding a husband to marry and have kids with as easy as flipping a switch at any point in their lives. So they think nothing of waiting until their 30s to actually get serious about the idea of marriage.
Women should really get serious about marriage the moment they are fertile.