It was a little trickier than I remember, they actively promoted illegal ways to obtain the keys, provided the tools to illegally bypass the DRM with them and (and this is what likely caught Nintendo’s attention) they were very actively monetizing it. This was enough to get Yuzu branded as an illegal tool sold to do piracy with.

Ryujinx was far more nebulous as few details were leaked, it seems there Nintendo just swung it’s big legalese dick around. Probably helped by the Yuzu settlement.