Because the DMCA is for them not us.

It should be required, by law, to accompany a DMCA claim with some kind of digital signature that can certify the issuer really owns the content (such as a company or law office certificate). Other than that, they're prosecutable as perjury, but in practice, no one ever inquires those cases.

Garry has now clarified that the takedowns were in fact issued by Nintendo, contrary to earlier reports.

https://twitter.com/garrynewman/status/1783501547361411494

Because copyright monopolists have trillions of dollars which they use to pay lobbyists and essentially buy laws such as the DMCA which says that you can issue a take down and it's up to poor sap on the receiving end to either submit or fight a costly legal battle to prove not just their innocence but their bad faith.

The barrier of proof for a bogus DMCA is incredibly high. Even something like "our system sends out 100k takedowns a day, so it had to be automaded and sometimes we face false positives" is enough to shut down a case.

DMCA has many problems and needs to be updated for 20 years now. Remember the DECSS issues faced?

I think it's only Nintendo that'd be able to go after someone sending claims in their name.

It'd likely be hard to find whoever sent a false notice on general, since there's no identity or address verification needed to send one.