"I use AI art because I can write but can't draw" is not any more acceptable to me than, "I use AI writing because I can draw but can't write."
Viewing post in Disappointed that "AI art" is permitted
But that's not entirely true... if someone has eye-catching art in their submission it typically will get more views, looks more professional, is seen as "better" than something with amateur art or no art at all.
In terms of the judging criteria it has to do with usability. If the art adds to the adventure, can set a mood, help the GM and players visualize... then it helps.
And if the art is AI generated, some take issue with it, while others do not. The reality is that many people participating in a game jam may not have the time to comb through all of the fine print, so they may not even see if it is AI art or not.