The output being created by a machine is not automatically disqualifying. e.g. PCM audio data is all created by a machine, but that doesn't prevent CDs from being copyrighted... because the input to it was highly human-created.

Ultimately it all hinges on the specifics of the training and how much human involvement was involved throughout the creation process. I suspect arguing this successfully in favor of upholding a copyright would be an uphill battle for many situations, but ultimately we'll need more court cases to know for sure.