Thing is, DMCA doesn't apply all over the world. There are countries where whatever electronic device you buy is actually yours and you're allowed to do whatever you want - including messing with the firmware. Also, I'd argue, the DMCA doesn't apply if you dump the firmware/keys for yourself only without distributing it.

That being said, it's unfortunate that these people are mostly in the US where the party with more money decides when a lawsuit is over and not some sane judge that just throws this case back at Nintendo. But after the stuff with Disney+ and the recent one with Uber, I'm not surprised at all anymore.