The purpose is no longer to detect possible plagiarism, but merely for the software to spit out the same answer when presented with the same text, therefore certifying its originality.
Warner continues this conversation on Twitter in the form of a thread. One thing that stood out to me was this:
When I've taught literature courses I made the writing explicitly about the intersection between the student and the text. They could not produce something without mining something unique to themselves. This still required the kind of analysis we expect in literature papers.
— John Warner (@biblioracle) September 19, 2019
This is something that he discusses in his book Why They Can’t Write.