There's some information that I need to memorize (how to use git, how to write code).
There are also and other things that are in the periphery of what I need to know, but can look up easily when necessary. These include things like my mother in law's mailing address, my coworkers' phone numbers, my wife's phone number, the population of the US, how to rewire a plug socket, and the recipe for Belgian waffles.
Each of those things would be good to know, but we can effectively offload it to external memory.
There are many developers who think looked-up knowledge is the same as knowledge understood as part of a wider conceptual framework.
They become annoyed during interviews when they are asked some concept and suggest "I'd just look it up on Google", which is fine for matters of programming syntax, but not fine where it reveals that a developer does not understand an important concept.
Yeah, all that stuff is stupid. Who the fuck cares what the capital city is for each of the 50 states? That's what atlases used to be good for, now it's an almost instant search in Wikipedia.
And again on the plane on the way home I said it to the pilot who was carrying a book into the cockpit.
And when my 18 year child went out driving for the first time on his own I handed him a book titled "How to drive".