You are absolutely right that there is a tendency for people to respond to a recommendation request with a book that is too much for the requester, and I've sometimes thought may have been too hard for the answerer on their first time through the material. I see that on /r/math, for instance, it seems to me. (That phenomenon needs a name.)
That said though, let me say that for me personally SICP was mind-opening. I think about it a lot; it has had a major influence on me. An example is that I am working on a Theory of Computation book and I am trying to emulate some aspects of it (while keeping the presentation accessible). I certainly will admit, though, that when I read it I expect that I was in a different place than the post's author or than the typical student.
That said though, let me say that for me personally SICP was mind-opening. I think about it a lot; it has had a major influence on me. An example is that I am working on a Theory of Computation book and I am trying to emulate some aspects of it (while keeping the presentation accessible). I certainly will admit, though, that when I read it I expect that I was in a different place than the post's author or than the typical student.