Was going to also post the same thing. It too is one of my favorite sci-fi movies.
I just commented before seeing your mention of it.
Although I didn't realize until I commented that Jerome Bixby the author of The Man From Earth was also a Star Trek writer.
Oh yes. I met them in person a while back [0]. Super nice people.
[0] https://twitter.com/synopsi/status/1188295183130955778?s=21
[0] https://en.wikipedia.org/wiki/The_Man_from_Earth