I guess I was surprised by this reaction simply because Luke's arc didn't seem that shocking to me. It was fairly close to what I had assumed after TFA. It didn't at all feel like the surprising "subversion" that so many seemed to see it as, so the outrage kind of came out of left field for me. Maybe it has to do with the fact that I never read any of the extended universe stuff so I didn't have any other grand ideas about what an older Luke would be like, I dunno. But Johnson's take on the Force and the Jedi is something that was touched on in the prequels but not in a remotely satisfying way, so I was very pleased he chose to explore it more through Luke in this film.