@davidrevoy
It's genuinely awful you have to deal with this, especially on such a regular basis. I think derivation is still fairly legally gray, though perhaps less so on directly feeding an agent a specific image to alter. It'd be interesting if the strongest point of violation is courts generally ruling AI output is not copyrightable, meaning it cannot follow the terms of being licensed as CC-BY-SA.

I'm sure malicious folks will still go against your whims, but publicly disavowing the use of generative AI will surely curb well intentioned folks, who are perhaps misinformed on the harms of generative AI usage. At the very least, I hope it gives you less headaches in your inbox; I'd feel so deflated seeing that so often.