I mean, many thought the same of Yuzu.

Problem is, Yuzu team were breaking other laws. They were tweaking their codebase based on leaks.

I would not be shocked to see Nintendo either attempt to un-GPL the code, claim some sort of copyright over forks, or even to maliciously inject new code in an attempt to gain access to user IP addresses and just send out letters to every Yuzu user. Nintendo really is that petty, look at what they did to Gary Bowser. They will 100% go after other emulators like this now that they know the developers will just give up in a week.

Do you know how much of society depends on GPL code? Every Android phone, every Chromebook, most servers and many billion dollar companies rely on GPL code. Nintendo attempting to un-GPL Yuzu will wake some sleeping giants, who will realise other people might attempt to do the same to the projects they rely upon. As a result the defence fund for anyone Nintendo goes after like this will end up VERY well funded. As in, make-Disney-shit-their-pants well-funded.

As for your point on Gary Bowser, you're kinda leaving out that Nintendo had a MUCH stronger case against him. Unlike emulators, the development of piracy modchips is very much illegal.