The user I was replying to wrote

> This kind of discussion is suppressed on HN

Typically people wouldn't use "suppressed" to mean: "there are disconnected users of this website who are, without coordination, independently flagging this submission in deliberate bad faith".

Typically "suppression" would refer to a coordinated deliberate act.

So I was simply replying to the most common interpretation of the user's words.

I understood them to be saying that a deliberate (and not accidental) attempt is being made to prevent "this kind of discussion" from happening.