Hopefully, it wasn't the success of Yuzu but the fact it was being developed by an established company which was accepting over $30,000/mo in donations for "internal" builds.

It's a lot easier to pressure a company that you know has a bunch of income, is firmly established in a country that recognises US copyright law, and makes a lot of money particularly on a legally contested technology.

They've gone after Dolphin before, but that's still up and going. If Ryujinx or some other Yuzu rewrite (a soft fork would be v easy to take down imo) goes down then I'll be proven wrong here