that's a conspiracy theory
The by far more common action is for the mods to restore a story which has been flagged to oblivion by a subset of the HN community, where it then lands on the front page because it already has sufficient pointage
> I’m referring to the actual moderators of this website removing posts from the front page.
This is what you said. There has only been one until this year, so now we have two.
The moderation patterns you see are the community and certainly have significant time factors that play into that. The idea that someone is going into the system and making manual changes to remove content is the conspiracy theory
It's not controversial to say that submissions are being moderated, that's how this (and many other) sites work. I haven't made any claims about how often it happens, or how it relates to second-chance moderation.
What I'm pointing out is just that moderation isn't the same at different times of the day and that this sometimes can explain what content you see during EU and US waking hours. If you're active during EU daytime hours and US morning hours, you can see the pattern yourself. Tools like hnrankings [1] make it easy to watch how many top-10 stories fall off the front page at different times of day over a few days.
[1]: https://hnrankings.info/