generation differences

Follow me on this one:

Perhaps in a hypothetical world everyone only married someone their age and had a baby at 25 (average age of first time mothers according to the cdc).

The baby gets born and 25 years later finds someone their age and has a baby.

If this continues for a while perfectly, Individual generations (25 generations) would be more similar amongst themselves than with any other generations because their genetics (and parental styles) wouldn’t be spread/shared across generations.