This tool's been fueling tons of false accusations in academia. Wife is doing her PhD and she often tells me stories about professors falsely accusing students of using ChatGPT.
A group of students at my university were claiming their papers were being marked by a LLM. They cited a classifier like the OP which they used on their feedback comments.
It isn't just this one. There are a hundred different "AI detectors" sold online that are all basically snake oil, but overzealous professors and school administrators will keep paying for them regardless.