This is because people are using the artwork as a proxy to praise or criticize the creator.
When they say that the work is intricate, showing great skill and perseverence (to pick some quality judgments), they mean that the artist has skill and perseverence. When that turns out to be an algorithm that is mashing up information from the training data, then people take that back; there is no artist there with skill and perseverence. The artwork itself doesn't contain skill or perseverence; it's just potential evidence that skill and perseverence were involved in its creation, which is not confirmed when it's an algorithm.
Nobody actually cares about the art; it's always about the person.
People idolize the arists, while pretending to be idolizing their works.
That's why an artist can commit "career suicide" with a neo-nazi rant, or possession of child porn, or whatever; it was never about the actual artistic artifacts.
Why was Bob Ross, the painter, regarded as kitch? In large part because he used tricks to create detail without deliberation; almost like an algorithm. You use this kind of brush, dip it lightly into white, dab it it a few times this way on the cavas and that way and, hey look, it's an ocean spray above the rocks: "anyone" can do it if they follow along. It's thew same thing: the dabbing thing and whatnot were like his AI; he just "prompted" the brush, make me a realistic spray and the brush did it with a trick.
Art has to be confirmed evidence of Hard and Deliberate Effort having taken place, using Skills that took Years of Practice combined with Talent to acquire; that's just the way it is.
Art fans are basically sports fans; art is a kind of sport, where any kind of shortcuts are like steroids, hidden motors and course cutting; those who retract their judgments believe that they have all of Honesty and Authenticity entirely on their side, because it's never about the Work by itself, but only circumstances of its creation.