Edit: I was wrong, read mistrial9 and chubots comments.
The general sentiment at the time was that it was rude, crude and unacceptable to monetize the open networks with ads, as it was clearly a "commons" and every single Western person was familiar with bill-boards along a highway, and endless commercials on radio and television.
It is quite interesting today to see the name of the man who "invented adwords" as I had not seen it even once before.
http://infolab.stanford.edu/~backrub/google.html
Currently, the predominant business model for commercial search engines is advertising. The goals of the advertising business model do not always correspond to providing quality search to users. For example, in our prototype search engine one of the top results for cellular phone is "The Effect of Cellular Phone Use Upon Driver Attention", a study which explains in great detail the distractions and risk associated with conversing on a cell phone while driving. This search result came up first because of its high importance as judged by the PageRank algorithm, an approximation of citation importance on the web [Page, 98]. It is clear that a search engine which was taking money for showing cellular phone ads would have difficulty justifying the page that our system returned to its paying advertisers. For this type of reason and historical experience with other media [Bagdikian 83], we expect that advertising funded search engines will be inherently biased towards the advertisers and away from the needs of the consumers.
That's pretty much exactly what happened to Google (and the entire web honestly) in the last ~10 years. I'd say that Google was doing a very admirable job of avoiding this bias from 1998-2008 or so -- both search and ads were good.
But basically the founders moved onto other things, handed search and ads over to VPs, pre-IPO employees left, etc. and the result was predictable. In large enough numbers, people behave according to incentives... it's basically "physics".
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Also I think Go.com is notable for inventing paid search -- it wasn't Google. There was a book that covered this history in detail -- I think it was one of the many books about Google.