Testing an AI writer and using an AI writer are not the same thing. I tested all of the ones that I could find well over a year ago when I saw more and more typists on here saying they were using AI for their Medium posts.
To me, that's cheating. You didn't write anything. A bot did. Yet you're getting paid and getting followers for work you didn't do. I asked Medium about it back then and never got an answer. So as long as people can take the easy way and make a buck they will.