I also agree with that, they’re barking up the wrong tree. The subject matter conveyed in conversation is too specific to just correlate words and hope that leads to an appropriate answer. Conversation is just not statistical beyond generic small talk about the weather. In addition, the problem of inconsistent personality, contradiction, and repetition, is created by the approach itself.
Having said that, I find this article opinionated and harsh. One example of what it calls “soul crushing dialogue” shows a program repeatedly saying “I don’t know what you mean”, but if you look closer, that seems to be a result of the user’s misspellings, omissions of subjects, and cryptic responses. I get it, Facebook is out to commercialise this so they want programs to handle all sorts of nonsense, but that hinders testing the programs’ technical capabilities.
Here is a paper describing the event with more detail: https://arxiv.org/pdf/1902.00098.pdf