ChatGPT is a machine built and operated by humans. If ChatGPT infringes copyright, then it is those humans who own and operate it who are infringing.
The fact that they built a complex obfuscated system that stores many copyrighted works in a novel way (model weights) and reproduces them incompletely or unpredictably when asked, doesn’t change the fact that they have built a system whose purpose is to infringe copyright.
It’s a little bit like saying I started the car running and let it drive off on its own accord in front of a huge crowd of people, I’m not responsible for the deaths because it was the car that ran them over and the car doesn’t have agency. The car wasn’t designed to kill and never intended to kill. But it’s still me who operates the car and should have foreseen the obvious consequences.
I don’t buy into any of these arguments that just because ChatGPT is very complex or mysterious that somehow the humans who built or are running it aren’t responsible for its actions.