If including a copyrighted work in an AI training corpus is theft because of its influence on some artificial neural net, then so is viewing it by a human being, whose memory is now somehow the property of the copyright holder, an absurd conclusion.
Well if we're concluding that training a neural net and a human mind forming memories is exactly the same thing, I'm looking forward to all their defenders agreeing that the neural nets should be held criminally responsible every time they generate an image deemed unlawful in certain jurisdictions...
Otherwise there's obviously a legally relevant distinction between a human mind which is ascribed agency to decide if and how to use its memories of copyrighted material, and importing into an information retrieval system which can't help but spit out transformations of parts of its inputs on demand, (including lossy representations of the Getty watermark if it's fed enough Getty material, or an exact facsimile of an image if that's all it's trained on...)
There's a massive jump in that logic, which is basically equating a large neural net to being exactly the same as a singular human being. If you ask me that is clearly not the case. They operate in entirely different ways and have very different properties.