Yuzu didn’t distribute keys. You had to obtain them yourself. The problems were that:
- They distributed software that would decrypt the games once provided with the keys (which is apparently illegal).
- They used leaked versions of TOTK to develop the emulator.
- They openly talked about piracy in their discord.
Note that I don’t actually know for sure. This is just what I saw online.
I believe it works by obtaining a real licence from Microsoft servers. Since MS wants to get everybody to move from 7 to 10/11 the only thing required to upgrade a win 7 install to 10 or 11 is an installation ID. And you can reuse the same installation ID infinitely.