What’s the evidence that Google Reader was “a popular service that was going strong”? I don’t doubt there were a bunch of people in tech and media who were and still are vocally angry, but I don’t recall data showing that Reader was anything but a niche product.
It wasn’t expanding at Twitter/Facebook rates but it was apparently growing on a continuing basis. More importantly, however, it was popular with communities with outsize influence – journalists, writers, bloggers, academics, librarians, etc. who used it to follow and share — so when they launched a really half-assed replacement (i.e. it didn’t even work on mobile) most of the people writing reviews and answering questions were starting from a position of something which was useful to them being replaced with a mess, and Google+ never recovered from that bad reputation.
Years later, I was at a museum/gallery/archive/library tech conference and the Google Cultural Institute folks were running their sales pitch. Multiple people asked them where their institution would be “when you cancel this like Google Reader”, a sentiment I’ve heard in enough other contexts that I doubt is fully appreciated by Google management even if it has been good for getting users to think about lock-in.
