I know that a request must be "under penalty of perjury". But that doesn't protect against fake information. Anyone, and especially parties outside US jurisdiction, (and even more so in countries which don't have an extradition treaty with the US) can contact or fill out a web form stating whatever is needed. They can even create a bot to do that automatically.
Why would someone do that?
Terrorism, racketeering and simple extortion, or just for fun / malice. The point is that removing content (even for a short while, not followed by any legal action) can be very damaging.
How is this different from other perjury threats?
When someone physically goes to court they take a chance, they can be arrested. It's also much more resource intensive. But fraud over the internet is much less hazardous (for the felon), and much easier.
EDIT
Apparently the question wasn't clear enough. I know that in a "normal" case, there is enforceable protection. That's the "perjury" part. That's why I put the word enforceable in quotes. My question is about the cases I mentioned above. I'm asking if there's any deterrent for those who give false information about themselves or who are not in the US. All as stated above.