AI has no idea what you're trying to convey through a picture. Imagine you're shitposting a "this is fine" meme with some bad collage on it, asking for a LLM to properly convey your take is just a fool's errand.
But I found that even that was not easy to do with "traditional" OCR, notes here: https://digitalseams.com/blog/image-transcription-humbled-me
Alt text is not there to explain the joke, that would imply cripples are stupid.
AI is fine, if you want to go against the trillions $ come back with a proof.
LLMs fail, wow easy to find, I'll bet alt text on random internet images fails at over 10 times the rate, most are null.