Japan is what you make it, just like anywhere else. I think many people become disenfranchised with where they are from and discover Japan and then think it's going to be some kind of utopia. It's not. It's just like anywhere else. People will be a bit standoffish to you if you don't speak Japanese. Japanese fear awkward encounters and a language barrier ranks up there pretty high on thinks they fear. That said, Japan has become so much easier to travel around since my first visit in 2003. Smartphones for use with translation and Google Maps for any and all train info is amazing. Making friends in Tokyo can be a bit hard if you don't speak Japanese. If you come to live here I would recommend finding a hobby club, sports club, etc. and make friends through that. Just striking up conversation isn't very successful for making friends here. This is where I think many people go wrong. Check out /r/japanlife on Reddit. Lots of good info there.