It was a stunt to show how you can bias your data to create your narrative. They specifically used a subreddit about death, then wrote an article with a headline about how using reddit as a source made a psychopathic AI. The point was that the headline is technically true but highly misleading because the data was biased, and the article itself focuses on that bias, but in a case of doing too good a job looking like the thing it is fighting, most people have just judged it from the sensational headline and decided "what is the world coming to?"
https://www[dot]theverge[dot]com/2018/6/7/17437454/mit-ai-psychopathic-reddit-data-algorithmic-bias
https://www[dot]theverge[dot]com/2018/6/7/17437454/mit-ai-psychopathic-reddit-data-algorithmic-bias