Well, what about the psychological side of things?
Could humans take even more (obligatory) education time? Even more time working? We are already seeing the bad economic impact of an older retired population that's being sustained by welfate and their own savings in some europeans countries. (see Portugal)
If society opted for longer productive life spans, it would come with a need to control population growth even harder, else t
Maybe people aren't actually bad at dating, but bad (or willing) at forming and keeping meaningful relationships.
From your question, it feels like you're trying to understand why people are bad at dating (as a means to form meaningful or lasting relationships), but the point is that most people don't want to form meaningful lasting relationships, they just want to quickly or efficiently satisfy their temporary and more superficial needs for bodily and emotional pleasure, and often they can do that without going into "efficiency" about how well they attract dates or partners.
So it's neither solution #1 or #2, but
Solution #3:
People just don't actually care about "mates" in the sense of the type of mating that leads to solid relationships, what they're seeking is to satisfy their own needs.