That is the industry that went away. A few of the little guys (myself included) survived the Mass Extinction, much in the same way that proto-mice survived the alien first strike that killed the dinosaurs.
10 years later, we still aren't seeing any of those giant Consultancies emerging again (at least not onshore). It's just a big mess of little shops. And many of us have product lines to smooth out the revenue curve.
Folks who don't understand a new field will throw money at it because they want a serious professional to hold their hand. As the old 80s aphorism put it, "nobody ever got fired for buying IBM"; an executive at an FT100 company, dabbling in the web for the first time, would expect to spend lots of money at the steep start of the learning curve. But once they began to get a clue about how difficult (or easy) the job really was, they'd start to play hardball.
And that's what the early web consultancies didn't understand: they were living on borrowed time, and basing their growth on a commodity that could only scale linearly (web developer/programmer hours).
There's no lack of hype in the current web, but that first bubble was really something to see :)
The truth is it's so big now that it (sadly) manages to sustain a fairly significant underbelly of complete incompetents along with all the qualified people.