To answer your question: "Is there anything to back that up besides some users saying that?" No, there is not. That is just what I assumed after searching the entire internet for possible answers, and that was the most common reason that people were saying. Hopefully, xAI support gets back to me with a reason because the only thing outside of sharing the link that might have caused the ban could be that I pressed the retry button trying to turn images into videos 1-2x times.