It’s not secret, because they’ll be provided an answer if they email the mod team.
It’s not free as in open source, because it isn’t available for anyone to download and study in full.
So, since it’s not secret, is it public, or private? Since it’s not published in full but any query of LIMIT 1 is answered, is that open, closed, or other?
Restrictions to publication don’t necessarily equate to secrecy, but the best I’ve got is “available upon request”, which isn’t quite right either. Suggestions welcome.
The opposite would be to show the author of the content some indicator that it's been removed, and I would call that transparent or disclosed moderation.
Interestingly, your comment first appeared to me as "* * *" with no author [2]. I wonder if that is some kind of ban.
[1] https://www.youtube.com/watch?v=8e6BIkKBZpg
[2] https://i.imgur.com/oGnXc6W.png
edit I know you commented again but it's got that "* * *" thing again:
"This domain is not allowed on HN" as an error message upon submission.
Re the 'delay' setting see https://news.ycombinator.com/newsfaq.html.
It's quite possible the reason the list isn't public is because it would give away information about what thought is allowed and what thought isn't.