- the women are competing for top ~10% of men, who almost always will have multiple casual partners at any given time because of this
- the (other 90% of) men are competing for the top 50% of women
It's a mess of poorly defined and misaligned interests. This leads to tension and stereotypes ("all men are assholes! all women are harlots!") and sexual inequality.
For me, and I suspect most people, it seems much better to just do the things you enjoy, be friendly, and find people where there is some mutual interest in spending time together.
Until the woman has to defend your eligibility against her female friends, comparing you to previous partners, current alternative suitors and male celebrities.
Because the majority of women is like that and unicorns by definition are hard to find?
One of my brothers in his mid 20s briefly dated some girl a bit older than him, maybe late 20s/early 30s.
When my parents found out, he got chastised for it (in a somewhat playful way albeit). They did not necessarily like this, the kicker is they have an 11 year age gap themselves, but it's my father who's older.