We mostly don’t know. But we do know they’ll take any & every opportunity to smear China, and they aren’t above just making random shit up, and the harder it is to call them on their bullshit the better.

China doesn’t play by the old-school spy rulebooks, intelligence officials say. It doesn’t seem to care if it is caught red-handed and, unlike Russia, it rarely makes efforts to swap its spies when they are arrested.

This sounds like made-up bullshit, and I doubt they feel the need to back up the claims, because who’s gonna call them on it? And who has the time & resources to disprove them? Even assuming every one of these hacks is real, I suspect many have no connection to the Chinese state. They’re just hackers hacking for fun or unsavory profit. But I can’t prove my hunch.