Abaay
Its against nature. Man is made to admire and go after something that is youthful & beautiful. Its connected to the animalistic need to pro create. The older woman as well is naturally made to dislike sex in her mature age. Anything less than that is abnormality.
Also culturally -- Younger and Older relation is sort of like a vampire inter-relationship. The older wants to live vicariously through the young. Men typically like this vicarious living .Therefore, men think twice before sleeping with an older woman, unless absolutely necessary, and then they have to hit the road fast the first opportunity they get! lol
But there is good news. There is 3% of men who are attracted to very old women. These men have low sexual libido, who are very close to their moms, who are highly intelligent. These men look beyond biology and the typical norm. (the president of France for example he is in his 40s, she is in her 60s