Pretty different from the blog post, but I've definitely had periods in (and out of!) my career where I learned a ton that weren't super-busy. I got to do some really high-leverage work in a strong environment with great colleagues, and the fact that I wasn't under a bunch of external/artificial pressure let me learn more (and accomplish more!) while still having plenty of time and energy for other things.

Seems like most people really overvalue pressure and long hours, when those are neither necessary nor sufficient—hell, probably harmful—for doing and learning a lot. I'm not entirely sure why, but I expect a cultural "no pain, no gain" attitude is part of it. People want to feel like the pain they went through was worth something, and we're conditioned that anything that's worth doing takes pain, and the two attitudes reinforce each other.