Pangram can sometimes flag human-written writing as AI-generated. Though in practice, the reason you're usually running something through Pangram in the first place is that the writing has no depth of insight and you already have suspicions due to other reasons. In that context, what almost always happens is that the person who wrote it will come out and say "no, I wrote it myself I just used AI for editing" aaaand, you pretty much have your answer.