Art theft
I mean, they’re not wrong but … since they’re also hacking people their motives seem kind of mixed.
They are wrong. Theft means depriving someone of having something, and that’s not the case here. It’s more a “they’re taking our jobs” kind of situation.
You forget all the images that “AI” models are trained on without consent or payment. Plus as you say, that training could result in the same artists losing work. Double theft, of IP and future income.