I was just re-reading Doc Smith's Subspace Explorers last night, and it occurred to me that if psionic powers existed, and if the model/theory he used in his book worked - a unity of sorts between the psychic's mental map and the real world - it would be significant evidence for living in a simulation. Maybe they were bugs, and they dried up because the simulation was debugged. Note that I don't think this is likely, the most likely explanation for psychic powers is still a combination of self-delusion and fraud.
(I'm sure you know this, but just to be clear, "self-delusion and fraud" is a fully general counterargument/explanation, and you likely wouldn't be motivated to use that counterargument/explanation unless you thought psi was unlikely for other unmentioned reasons.)
[Post redacted 'cuz I unfairly and carelessly misrepresented someone's views (Eliezer's). The messages of this post was: disbelief that aliens visit Earth in spaceships is a bad reason not to look into ufology. My apologies for this ugly post.]