I think there are 3 main rules in society:
1. As long as women or men are adult deemed by society (for example: 18 years old), anything is fine, even if 18 year old woman paired with 74 year old man. Age of consent rule.
2. A man should not date a woman younger than his age / 2 + 7. So a 74 year old can only date the youngest woman with 44 years age. Creepiness rule.
3. A man should not date a woman younger than 25 year old because the brain is not fully formed until 25 years age. Unless the man is more or less 25 year old himself. So a 74 year old man can only date the youngest woman with 25 years age. Brain fully formed rule.
Of course there are edgy case rule. We call it Romeo-Juliet rule (no more than 4 years difference). 16 year old woman should not pair with 74 year old man but if the man is 18 year old, that should be fine.
