I have no idea what you are talking about. I remember web search before Google existed. PageRank was a massive, huge improvement in search results. Literally night and day. There’s a reason why Google is a verb now.
The emphasis should be on the 'was' there. PageRank was so much better than the competition that it gave Google an effective monopoly on search. That lack of competition meant Google could focus on how to get users to click on ads displayed alongside search results rather than how to return better results than the competition. Consequently now Google search is only OK at returning what you're after, and the page is 50% ads.
Google hasn't been coasting along on the success of search for decades though thankfully. A lot of Google tech is very, very good (Gmail, Docs, YouTube, GCE, etc). Search is still better than the competitors but that's only because there's only really Bing. The problem is that it's really only Search that drives revenue.
I strongly believe that if anyone made a better search engine than Google, and consequently Google's ad money took a nosedive, Google would be faced with an existential crisis unlike any other business in history. If Apple are building the search product they're rumored to be building all Google staff should be very worried because no jobs will be safe.
Larry ended up making PageRank because the number of sites that linked to a site was the best measure when all links were created by humans and the Web wasn't commercialized. It was an automation/algorithm for the measure most link lists/curators used at the time to determine precedence order and importance, but for one thing, that measure only works when the sites themselves are vetted first (you wouldn't get a link on 'Best Science Links on the WWW' unless the author of the site liked your site and was convinced it wasn't full of crap).
More broadly, as someone who agrees with OldTimeCoffee but thinks it wasn't purposeful, I'd say that search and web crawlers won an early war I'm not sure they should have won. We can't turn back the clock, but I do wonder what it would have looked like if Google were founded 17 years after the Web started and not 7.
It's a comparative statement in response to 'twitter is killing the web'. Twitter has no impact over the web. Public discourse, yes absolutely. But it isn't impacting the web in the same way PageRank (or Google Search more generally) has changed how the web is made.