Is there any way if I can find out why my submission is flagged? The last thing I submitted was also flagged (and then unflagged), but I have tried to abide by the submission guidelines.
Users flagged it. We can only guess why users flag things, but in this case I suppose it might have been a combination of users who are fatigued by this general topic having been repeated so frequently in recent weeks, and users who agree with the decision to take down the interview and don't think HN should have a thread about it. As I said, though—those are just guesses.
In the meantime, someone else reposted it and it was on the front page: https://news.ycombinator.com/item?id=23258432. But since this post was first, I've turned off the flags on it and merged those comments hither.
However I do think there are "flag mobs" which increasingly flag posts they don't agree with.