Let alone how are they affording to index and crawl all those pages, which is still only a tiny fraction of the entire internet.
Maybe search engines are a dying breed, and we'll have to rely on AI and word of mouth for information soon.
Which apparently worked well for quite a long time, but also dangerous over time because you don't really know why something now ranks well, or doesn't. The best you can do is have human raters score various searches, tweak a bunch of weights/knobs, and try over and over again.
Meaning, perhaps it's not that the internet is too big, but that the overall model is too big and disjointed to manage well. Also, if you're on this team, you're competing with the ad side that's continually pushing the organic results down the page, where they matter less. A lot of fussy tuning around "quaint hotel in Paris" seems wasted when the end user is 3 scroll events away from the organic results.