Eh, I wasn't even referring to forgetting how to write bubble sort or hashmaps from scratch. But just being able to reason about different algorithmic solutions

Eh, I wasn't even referring to forgetting how to write bubble sort or hashmaps from scratch. But just being able to reason about different algorithmic solutions to a problem, and intuit something about their complexity and requirements. Thinking back to a recent-ish discussion here about the (very elegant and efficient) algorithm behind Shazam, and some of the comments here being along the lines of "haha, that's so quaint, nowadays you could just use a neural net". Nevermind how that would even work as well. Or programmers excited about neural networks forgoing the much simpler, and in many cases completely sufficient, computer vision algorithms built into OpenCV, in favor of trying to train their own model from scratch.