I personally guarantee you there's original art. The sketches are on his patreon page, and they look almost exactly the same as the in game art. My guess is he uses AI to generate the backgrounds but the characters are like 99.9% based on his hand drawn designs. Once something gets labeled AI it's ostracized by people immediately. If the mods have investigated this and found it doesn't need AI tag then that's that. I don't get the urge for people to come in here and crap all over something they don't even play. This community tribalism is exhausting.
Tribalism? Look, I just asked why it wasn't labled. There's clearly AI involved and they admitted as much in their steam page. Not only that, but if it was JUST backgrounds, you can specify that on Steam aswell, but if you don't, it's because they can't deny it to steam.
As far as the claim of Tribalism, I won't go off the rails and bestow upon you all my beliefs, but to make it short, AI, whatever you think of it, is a threat to all creative expression. I'm not exaggerating and there are people 100 times smarter than me echoing this statement. THAT is why people don't like AI.
Now, do I think AICG art is gonna be the end of the world? Hell no. But calling an existential and unsolved issue people just banning together to hate on something is a bit undercooked. Think about WHY people might dislike it, don't just strawman them and calling it Tribalism.
Enjoy your AI, i just wanted clarification because for me, it's not good. That's it.
Edit: One last thing, it's trained on the Summertime Saga art, not "their own"