The only thing which killed Reader was Google management trying to make Google+ popular. Reader was extremely popular (and well outside of IT circles - I still hear from librarians, scientists, policy wonks, etc. who are bitter about Google taking away their information filter. In DC it was common to see other people on metro in the morning with the popular mobile apps open, just like you now see the Facebook blue) and the social network there was quite active until the day Google shut it down and forced everyone into the alpha-quality Google+.