That's the way the world is. Fortunately, there's good stuff, too. My final beef with usability gurus is that they don't take into account that there are, well, stupid users. There are folks who have trouble using a dictionary let alone navigating a Web site. They easily get lost in the real world.
Stupid people skew results.
A site doesn't have to work well for everyone. At an ACM Hypertext Conference 10 years ago, a professor made all kinds of hypertext design claims based on a study involving 10 graduate students asked to solve a computer problem using an online Unix manual. None of the students were versed in Unix and they didn't have an actual problem of their own to solve. I was amazed he had the nerve to make any claim based on such an inappropriate test group. Usability guidelines should recognize that our user experience is very limited.