I think those people may not have actually ever used Houdini. Another thing is that it is very different from other, more traditional apps.
The thing is that, it is not Modo. The modeling tools need work, but they have improved it allot with the H15 release. One more problem I see is that people get very complicated when they explain it - there are few beginner courses on it that are easy. I think 3DBuzz has some older courses on it that may be useful.