'Tainted' would be the accurate word
Well, consider as noted above that Photoshop contains AI tools, some of which seem fine to me. For example, a tool that can automatically identify and remove so-called "distractions", e.g. removing power lines from a photograph so that all you see is a clear blue sky. Is that "tainting" the art? It's still a photograph taken by a real human being, and the removal of such "distractions" is a laborious but not particularly challenging activity. I don't consider that sort of thing to have "tainted" the art in question, and instead see it as the proper and well-reasoned use of AI in art: to simplify tedious tasks
for artists so those artists can save time and focus their effort on the things that really matter. I imagine even for purely drawn art, removing "distractions" could have uses speeding up the process of going from a sketch to a work-in-progress, for example.
I don't think there's any way we can meaningfully prevent this sort of thing from happening, and I'm skeptical that it would even be
good for digital artists to pursue such a policy regardless. But tools like that are a far cry from stuff that whips up entire images (in many cases, by having used scraped--and thus stolen--artwork from the Internet).
"AI art" is not a perfectly simple binary of "absolutely nothing AI involved whatsoever, and thus acceptable" vs "literally any amount of AI involved at any point whatsoever, and thus completely unacceptable". It is more complex than that. I absolutely agree with you that most AI art is trash, that using AI-
generated art is a serious failing on the part of the creators of a work, and that the presence of even a single piece of such work does tarnish the whole product.* I am simply saying that there can, in fact, be some sense in which a work actually made by a human being--
not AI-generated--could in fact be "enhanced" by AI tools in ways that aren't awful bull$#!+ and are instead reasonable developments of new technology that can help skillful, trained artists make more art.
*For anyone who thinks this is excessive, imagine if someone tried to explain to you that there's nothing wrong with having a
single blood diamond in their diamond necklace. After all, it's just
one blood diamond, right? It's not like the whole necklace should be considered to have contributed to the slaughter of innocent people just because
one diamond might have done so. That would be
unfair to all the other, perfectly-legitimate diamonds and the people who cut them, who mined them, etc.