It is current known behavior. If an item gets five or six flags it will plummet. I've done experiments, I know this to be a fact. It doesn't require any intervention by moderators or anything else.
The severity of the hit on ranking was introduced some time ago - I can probably track it down if you like - but I doubt you'd take my word for it.
And if you'd care to check my posting history you'll find that I've spoken out against this several times, but you're clearly not interested in facts or evidence, you're clearly just annoyed that your posting has fallen off the front page.
And yes, this comment is snarky, and no, I'm not going to edit it to be milder. I'm annoyed at your tone when all I'm trying to do is share with you with the knowledge I have accrued over many experiments on the topic.