the human still made the prompt
What I can guarantee, is that series of prompts itself would be copyright-able. (The series of prompts that ultimately created the image.) No matter how little they may weigh any one of those prompts in isolation. That is, assuming the EULA of the LLM doesn't require you to essentially place your prompts in the public domain.
And of course,
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everyone reads the EULA. Right?
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