Yes, I read the article. Did you?
> The average participant scored 60%, but people who hated AI art scored 64%, professional artists scored 66%, and people who were both professional artists and hated AI art scored 68%.
> The highest score was 98% (49/50), which 5 out of 11,000 people achieved. Even with 11,000 people, getting scores this high by luck alone is near-impossible.
This accurately boils down to "cannot reliably be binned as AI-generated". Your objection amounts to a vanishing few people who are informed that this is a test being able to do a pretty good job at it.
If 0.0005% of people who are specifically judging art as AI or not AI, in a test which presumably attracts people who would like to be able to do that thing, can do a 98% accurate job, and the average is around 60%: that isn't reliable.
If that doesn't work for you, I encourage you to take the test. Obviously since you've read the article there are some spoilers, but there's still plenty of chances to get it right or wrong. I think you'll discover that you, too, cannot do this reliably. Let us know what happens.