I believe that the answer lies somewhere in the middle of: Being able to learn guitar without music notation and the fact that guitar is not the easiest instrument to learn reading notes with and the fact that 99% of guitar driven music in not notated (except classical).
I believe that reading music notation is a good thing to have, but on the other side in my 17 years (10 professionally) i NEVER got to studio and was given a lead sheet to record or play or what ever. In stead my studio time was more like this:
Producer: Here's the song, i need it to be like this and this, do your thing with it.
Me: 'Ok'

This is probably the main reason for standard music notation not being more popular with rock guitar.
But I don't think that making fun or even disrespecting other guitarist who invest time in music reading skills should be laughed at. This is bizarre and IMO act of an ego.