(author here) I was hoping I would have time to write part 2 of the FAQ before this hit HN, since that is definitely a FAQ.
tl;dr I used Python for prototyping; it will be removed.
Consider it an implementation detail -- building and running Oil does not require Python, as a portion of the interpreter is bundled in the tarball. Python 2 vs. 3 doesn't really matter. It was in Python 3 at one point.
More discussions here:
https://www.reddit.com/r/ProgrammingLanguages/comments/7tu30...