Sure. But the fact is they broke current existing laws, with known punishments with precedents. Same as a new law doesn't retroactively punish someone, then a new law shouldn't absolve someone before it's passed.
The law they broke was pirating the materials, not training per se, even though training is what so many people object to: the judge ruled that actually training a model, when the materials you used were ones you otherwise had lawful access to, was not a breach of law.
IMO, the laws need to change to reflect what tech can now do. This wouldn't be the first time, copyright law has had to shift several times before as new means of reproduction are created.
* the Anthropic one
The more interesting question is IMO if AI training actually falls into one of these cases. You can read a book and also copy it, but you do not do because of the law. However, you have the ability to do so. Is having the ability to do something already forbidden?
It's like if you read a plumbing book and then made YouTube videos on how to fix a sink.