Good grief, a Lamarckian! Quick, hide the silverware! :)
>> Unless some gerontocracy weirdly starts freezing the eggs of
>>very-late fertile women and has them (1) fertilised with old men's
>>screened sperm and (2) preferentially implanted into young women.
>(2) Why younger women?
If you want ova from the long-lived to supplant those from the young, you'd
need to persuade lots of the young to forego using their own youthful ova
and host spare gametes from the Darwinnowed old. Plus the advantage, of
course, that youthful wombs are better able to carry healthy babies to term.