There are still roughly 4 billion men on the planet to choose from though, so even 1 in a million with 100,000 women competing for the same thing is doable. It's really not the catastrophic math you claim here.

Secondly, dating is a binary matching mechanism. It doesn't matter if he "only wants" someone shorter, younger, and whatever than him. Unless attraction gets activated on both sides, nothing is happening without settling under some form of coerce, duress, or force whether that's mild like societal pressure or severe like physical assaults of some kind.