Quite a few cultures worked like this. Minor issues of "honour" would turn into persistent and violent multi-generational vendettas. Unfortunately, violence isn't necessarily a problem for social cohesion. It makes your culture a horrible place to be, but it doesn't keep humans from breeding successfully.
Re: memory, I think it's more likely that a better memory would take extra energy and perhaps a different brain structure, but would add no obvious survival benefits.
Early humans basically needed enough memory to find their way around an environment, to recognise each other, and to know a few heuristics for group values and survival practices (often camouflaged as myths and stories.)
There was no need to learn every possible back-of-the-book calculus formula or the entire syntax of Haskell. From that pov, human memory is already an order of magnitude better than it really needs to be.
Interestingly, some cultures were allegedly much better at memory than we are. Supposedly epic poets and druids endured long and incredibly arduous trainings with huge amounts of rote memorisation.