It depends on who’s doing the flagging, trusted users with more accepted flags have more weight to their flags: User Reputation and Flag Priorities
Is your intention to disable this? if that’s the case, it’s been requested before but I don’t think it ever ended up being implemented: Prevent content hidden by flags from being viewed
Right, they’re “silenced” this is controlled by the settings num users to silence new user and silence new user sensitivity
Sensitivity (in this case the hide post sensitivity setting) adjusts how much “flag weight” is required to hide the post. With “high” sensitivity, less “flag weight” is required to hide a post. This could mean fewer overall flags, or flags from users with less flagging reputation, could hide the post.
You can choose low/medium/high sensitivity, but you can’t adjust the sensitivity levels more specifically than that without a custom plugin.
So in this case, if 1 user with a good flagging reputation flags a topic… it won’t automatically be closed until 5 unique users flag it, because num flaggers to close topic is set to 5.
A lot of this is also further clarified in Discourse Moderation Guide