search for some exotic aircrafts on google (e.g. "Polikarpov I-3", "Polikarpov Il-400") - all you will find is wikipedia, scale-model ads and the odd pinterest (which isn't usable without an account and often doesn't show what was advertised on the page). I saved some pics when I was building the scale model some years ago and I'm unable to find half of them in a google image search today after scrolling so far that google is putting in non-I-3 polikarpovs for like all pictures... Also I think there was at least one "book" on the type but I'm unable to find any in the first 10 google search pages (who does that today...). For the latter I've had "bookmarked" an altervista-blog full of pictures - it's still ranked high in pictures, but basically invisible in search.

Duckduckgo is worse, it only has wikipedia-fakes...

And after this small experiment I'm reall frightened and staring at my bookshelf for resolve, in parallel searching for the HN article where people recommend "civilization rebuilding" material...

Not a direct answer to the question, but something I don't see discussed often enough: "It seems that Google is forgetting the old web" - https://news.ycombinator.com/item?id=19604135