I think Yahoo faded into irrelevance since it viewed itself as a media company and not a technology company.

Many internet companies fancied themselves media companies in the 1990s and 2000s. They all are on the scrap heap now, some examples: AOL, Yahoo, Excite@Home, Lycos, iVillage, About.com.

The companies of the time that fancied themselves technology/infra/logistics did well: Google, Amazon, eBay/PayPal, Salesforce, Akamai, DoubleClick.

Of course any lists like this have selection bias, so maybe I am wrong.