Code too.

I work with programmers and it's not uncommon that they can remember with shocking detail about code they've written in the past.

Someone might mention an issue that has cropped up and they'll stare off into space for a few moments and actually remember where that issue stems from in the code, because they remember writing it like 8 months ago.

This skill will be lost when AI is generating all code, we'll be stuck in a perpetual loop of having AI keep track of the state of the code in order for AI to extend and maintain it.