Did they deploy their AI in Europe? The AI trained on stolen data? It's like saying that you pirated a Disney movie in Europe and are selling derivative work from that in the US
The French punishers can sue Facebook in the US for violating their copyright. But since Facebook also operates in France, they can sue them there. It's that simple.
Copyright law is pretty powerful and generally global. If you write a book in France in French, I can't translate and sell it in the US.
So the punishers can sue in the US but they'd probably not win. Facebook operating in France means it is subject to french laws and can be sued there.
I assume he meant that just because someone believes in something separate from their scientific work doesn't affect their credibility.
An easy thought experiment is if an astronomer believes that when an ostrich is scared it buries its head in the ground. Does this affect their work?
If a surgeon believes in destiny doesn't mean that their work is subpar or that they sabotage their work because it might be someone's destiny to die.