Why we are still a long way from a 'killer' chatbot

It all started with a conversational interface, and then bots just took over the debate. Even in this great piece, while Dan Grover mentioned the ubiquity of chat, he also highlighted the fact that we should recognize the limitations of pure text-based input method. Looking at the history of bots, I struggle to see bots overtaking the streamlined GUI experience even now -- here's one recent subpar experience out of many. There's a good reason why we accepted the web and made it part of our everyday lives. It's very naive and sometimes bordering funny to think that bots will be panacea to everything we do in life and will take over humanity one day.