If they're just a bunch of common crimimals from China or Russia, I doubt they'll appear in court.
American courts are real scary when you live in a country that works together with the USA, but if you don't, all you need is to make sure your crimes aren't worth starting another invasion over.
The ones who've been unmasked haven't been sophisticated criminals, they're literally Discord teens trying to outdo each other.
Some have been American, others British, French, and Brazilian. At least one has been extradited from France.
It's a pretty odd community. I would expect most of these kids are smart enough to work a regular job when they graduate, it's wild what the allure of clout will convince one to do.
Not saying he had anything to do with this particular hack, but I doubt the ones within reach of the American justice department would be dumb enough to actually threaten the FBI like this.