Well, if we're going to have the conversation: so what if it were AI? Shouldn't the question be around correctness and good pedagogy? Shouldn't the question always be about vouching for those things? If it's actually done well (e.g. they were able to generate better illustrations than they otherwise could've), why exactly should someone think twice?
The author put his name and reputation to it. If it's excellent work, it's excellent work. If it's slop, it's slop.
The author put his name and reputation to it. If it's excellent work, it's excellent work. If it's slop, it's slop.