IANAL either, but filing a DMCA takedown request to claim copyright infringement where there is none is always perjury. You don't have to claim you own something someone else does, you merely have to claim infringement where there is none -- that's far easier to mess up.

So using a DMCA takedown request because of a trademark infringement if there isn't also a copyright infringement would be perjury because you're making a bogus claim. AFAICT this would only matter if both sides ended up pursuing legal action (i.e. the DMCA counter-claim is resisted).

The only example of DMCA abuse being punished I've seen so far is the infamous YouTube drama between thunderf00t and VenomFangX (who ended up reading a prepared statement as part of an out-of-court settlement with tf00t to avoid facing legal consequences).

I think most people aren't willing to actually sue DMCA trolls or are unsure about their actual legal position. It's certainly understandable why a company like Google might be more likely to just follow the rules instead of taking a stand as long as they're not affected directly. And tools like YouTube's automated content claims completely circumvent the need for "content owners" to invoke DMCA and risk legal consequences.