Films usually do not have “answers” when it comes to interpreting them. We can give our opinions and make arguments for certain things, but there’s no finite, definitive answer, and if there were, films would be boring. Even stories that are allegorical and have 1-to-1 analogues still have life and room for interpretation.
So just because Stanley Kubrick is possibly on record giving his thoughts on the ending of 2001: A Space Odyssey, it doesn’t mean the film has been definitively answered and concluded. ScreenCrush and Cinephilia & Beyond have come across a YouTube channel with footage from footage is from filmmaker Jun’ichi Yaoi, and in the documentary Yaoi was making, he interviewed Kubrick on the phone (supposedly) and gave his thoughts on the ending of 2001:
I’ve tried to avoid doing this ever since the picture came out. When you just say the ideas they sound foolish, whereas if they’re dramatized one feels it, but I’ll try.
The idea was supposed to be that he is taken in by god-like entities, creatures of pure energy and intelligence with no shape or form. They put him in what I suppose you could describe as a human zoo to study him, and his whole life passes from that point on in that room. And he has no sense of time. It just seems to happen as it does in the film.
They choose this room, which is a very inaccurate replica of French architecture (deliberately so, inaccurate) because one was suggesting that they had some idea of something that he might think was pretty, but wasn’t quite sure. Just as we’re not quite sure what do in zoos with animals to try to give them what we think is their natural environment.
Anyway, when they get finished with him, as happens in so many myths of all cultures in the world, he is transformed into some kind of super being and sent back to Earth, transformed and made into some sort of superman. We have to only guess what happens when he goes back. It is the pattern of a great deal of mythology, and that is what we were trying to suggest.
And that’s one way to read the ending! I’ve always taken the Star Child as a more nefarious entity, one that symbols rebirth but also his ominous place over Earth as somewhat threatening in that his new evolution requires the death of humanity just as his the Star Child’s birth required the death of Dave. But that’s the fun of 2001 and other Kubrick movies—they’re open to interpretation and just because Kubrick had an explanation for the ending, that doesn’t mean the discussion is closed. It just continues.