I think the banning AI art, or any models that use the training of data that wasn't explicitly authorized, is a really bad idea for several reasons. I'll list them below.
For starters, if we follow that rule to the letter, should the translated Chinese mods be banned too? How about mods that translate Starsector into other languages? If the translators used DeepL or Google Translate then they would have used an AI that was developed using unauthorized text samples. Most machine translators are guilty of this. Speaking of the Chinese, I doubt that they will abide by these rules so their mods will get even harder for us to access and that's not something good for the western playerbase in my book.
I also have a bone to pick with the kitbashing analogy. If someone makes a mod that has, say, Homeworld inspired ships (like that old mod did), is that "kitbashing" just because it uses the same style? It's obviously not and that's basically what the AI model does. It's very similar to how humans develop our styles. We see things, we are inspired by things and then we make something new that originally was something else. Inspiration and learning on from samples is not the same as copying and pasting literal chunks, which is what kitbashing actually is.
Another problem you'll run into will be, well, the drama. Once this rule solidifies there will eventually be some accusations of people using AI art or whatnot. Bad actors will try claim generated content as their own and the moderation team will have their work cut out for them trying to prove what is AI art and what isn't.
Finally, I foresee the modding community becoming even more fractured than it already has become. There are the modders here, the unofficial Discord, the Chinese modders and their forums, Corvus, Nexus and those in anonymous image boards. The banning of some controversial mods has already caused some splits, but this? It's much bigger than anything that has been done before. It's very much possible that the central modding hub will move away from the forums completely and I'm not sure that will be beneficial to the game nor the community.
All in all, you should let the lawmakers do their jobs and not jump the gun on the issue. I fail to see why a "remove if requested" system wouldn't be inherently superior to causing all this strife.