Realism>
As for what Japanese people think abut Japanese hip-hop, honestly, I don't think a lot of people know much about it at all/are aware that it exists (especially the artists mentioned in this thread - I consider myself very knowledgeable about the J-pop/hip-hop music scene, and even I don't know a lot of the artists brought up in this thread). It's not common to see hip-hop artists on music shows, etc, aside from a small handful. So I think that a lot of people really don't have an opinion either way, since they don't know much about it to begin with. I would say, like you mentioned, that it's a fairly small sub-culture. 