If Fumbling the Web has to be about one organization, that organization should probably be Yahoo!.
But FtW isn’t the story of one organization. The web isn’t a product, like the PC. While Xerox may have had the personal computer within it’s grasp, no one organization can grasp the web in a similar manner.
The web is a platform, not a product. The PC is both product and platform.
Here’s a one-paragraph explanation of the rise and fall of Yahoo!
[T]he only reason it ever succeeded in the first place was because it solved a global problem that lasted only for a moment. The early internet was hard to use, and Yahoo made it easier. Yahoo was the internet. Then the internet was flooded was capital and infinite solutions…
That’s from Nicolas Carlson’s Marissa Mayer and the Fight to Save Yahoo!. It’s mainly a book about Yahoo, despite its title.
The quote implies, accurately I think, that the web presents too many problems and solutions for any one organization to hold securely. So it would be inaccurate and unfair to say that Yahoo fumbled the web in the same way that Xerox fumbled the PC.
It might be more accurate to say that Yahoo stumbled, and never established a firm foothold on any part of the web. So Yahoo belongs in FtW, but is not the tragic hero in the way that Xerox is the “hero” of FtF.