On the one hand, using works without consent or attribution is bad.
On the other hand... This is exactly how humans train to become artists: by studying and remixing the art of others.
I think the lawsuits have a case if they can prove copyrighted images were taken and used directly in the commercial product.
The moral arguments about AI and it's use and abuse are broad and difficult, because they rely on the intent of the end user rather than the developer of the tool to prove an argument has merit.
I personally don't like AI art, but I can't declare that it's the devil's tool and should be purged with fire. I only think it overall will be a net negative, like I feel with AutoTune. It cheapens the artform.