I think that you're right. I haven't read the book, but I've seen the movie (and others). A buddy of mine has the book, and I get it when he's done.
People are going into an extremely hazardous situation and they don't have the correct tools. Tools being physical strength and technical ability.
Have you seen the picture of Mallory's body on Everest? He's been up there for 80 years, and still has more muscle mass than most of the people climbing today!
I really enjoyed the book. Sandy Hill Pittman, in particular, comes to mind as someone who couldn't even take care of herself much less anyone else. Krakauer alleges (and Pittman denies) that she had her a sherpa short-rope her up the mountain for until he was so physically exhausted he couldn't do more. It's that kind of person who must be a huge liability to everyone on the mountain...