As humans continue to develop our now mostly metaphorical but maybe someday literal exocortices they will grow new pathways, new weights. Yes some capacity will be pruned, I can't remember as much Hellenic poetry as, for example, Homer (ÎOEμÎÏÎÏ), but I have a lot of memories he doesn't... like how to operate a car, ps5, navigate the web, find my way around Skyrim, or have useful conversations with AI agents.
Someday hopefully I will have a BCI or artificial cortex I can modify as I choose to, for example, make me less autistic or increase my enjoyment of life or make me better at some skill or even learn Kung fu by downloading it ðY.
So what? Neural nets adapt... as they always have...