Google was all about crawling and building up the biggest dataset going.
Both approaches were victim to keyword stuffing (lots of keywords at the bottom of the page and if you were lucky it was in a marquee tag).
Pagerank was a pretty decent extra value with a relevance score to promote trust worthy sites. However there were similar techniques like hubs and authorities from kleinberg.
On a side note his old research students / postdocs ended up leading key initiatives at FB newsfeed and Pinterest discovery.