On the Nintendo Switch, it allows you to mount your console as an SFTP device and wirelessly transfer your screenshots without even turning on the console. Pretty fun stuff, especially in the motley years of 2017-2019.
What kind of new-fangled hack is that? Here in Switch-land we just use a bit of tinfoil for our piracy needs.
I believe the hardmod is a voltage glitching exploit, as described for the Vita here: https://yifan.lu/images/2019/01/Injecting_Software_Vulnerabi... . It is able to inject code through the onboard memory then load a payload from a memory card rather than USB.