Chatbots are almost a hype cycle on top of a hype cycle. Deep neural networks gave us AI as a hype cycle, someone imagined what they thought AI could do and thought that could be used to prevent people from talking to a real person, leading to cost savings, and so we have hype around chatbots built on a foundation of hype around AI.
The reality is, AI doesn't do what people think it does, and people call in to get a sympathetic human assessment of their issues, not because they're illiterate. So chatbots have no future outside of customer hostile applications that think people will keep paying no matter how disrespectful and unhelpful support is (see Uber). Unfortunately, this seems to work for a lot of companies.