Despite what's said in the title article, I think they have it wrong. It's not "too much technology for one man to handle," nor the "underwhelming dot com bust" that has killed the webmaster, it is the absorption of webmasters into the traditional corporate structure.
In order to be a webmaster, it's assumed that person not only knows the Web and the website, but they have some control over the latter. When webmasters became gainfully employed by corporations, they never got high tier positions, and in many cases, webmastering was something given to the lowest form of life in the company. Quickly, all control over what was going on with the website was out of their hands, and they were a "webmonkey."
Today it doesn't matter what webmasters know or don't know about how to do websites well (for those few that did), because it's not for them to direct much of anything. Webmasters were never destined to become bosom buddies with the existing management class, and there - you have the death of the webmasters.