Being really good at ctrl+F / LLM is not the same. I learn a lot just browsing through documentation, without searching anything in particular.
That's the big issue with LLMs as of now; They reflect their American creators and never want to admit when they just can't answer a question. CTRL+F will in fact give me 0 results, which is more useful than a wrong result.
However, as a non-native speaker, I really like the fact that I can give the LLM some description of a word that I don't know and it'll figure it out. "those fruits that are kind of bitter but also make my tongue feel like it wants to curl" (= "adstringend" [sic] or so, but who remembers that word or can spell it correctly?)
LLMs are basically like all those type-correction algorithms on steroids. Very helpful sometimes, even if it means I have to doublecheck their output.
need is a strong word. Do you need to be able to do ctrl+F? Not really, you can just read it all. But maybe it's easier to do ctrl+F. Same with LLM. Just imagine it as a fuzzy ctrl+F. Can be useful.