I think it also comes from the customer side... I continue to see a lot of behavior in large enterprises that seems to believe anything of *value* (not just cost, mind you) should by definition be big, complicated, and even cumbersome.
Really. I think the portal vendors, like other kinds of vendors, are just capitalizing on these behaviors. "Selling" something as simple as a Wiki, or even as simple as Smalltalk, is *more* difficult than selling the more complicated and costly approximations.
He's got a point there. How many applications that ought to be simple end up being massive 3 tiered monsters? How many people reflexively dismiss a simple client/server solution to a problem, because clearly you need a scalable N tier architecture - even in cases where the number of end users will be small? face it - developers absolutely wallow in complexity...