[joe_guy]

What you're thinking of on the Nintendo switch is a recovery mode. Every (most?) modern systems have something like this. It's a lower level area that allows you to fix issues in the higher level areas, even when that's broken (ie, a failed system update). Your iPhone, android, and smart TV all have this.

That being accessible wasn't the mistake. It was all properly secured. It rejected your commands and everything has to be signed by Nintendo's private key. But Nvidia firmware had a buffer overflow bug inside of it that allowed arbitrary code execution.

More details: https://blog.gistre.epita.fr/posts/victor-emmanuel.provost-2...

Bunny, the person who originally hacked the Xbox also wrote a great book on the subject they've since made free: https://bunniefoo.com/nostarch/HackingTheXbox_Free.pdf

If you enjoyed that book they have written others.