Have there been any US ruling stating something along the lines of “The training of general purpose LLMs and/or image generation AIs does not qualify as fair use,” even in a lower court?

Hell, that article is also all about Google Books, which is an entirely different beast from generative AI. One of the key points from the circuit judge was that Google Books' use of copyrighted material "...[maintains] respectful consideration for the rights of authors and other creative individuals, and without adversely impacting the rights of copyright holders." The appeals court, in upholding the ruling that Google Books' use of copyrighted content is fair use, ruled "the revelations do not provide a significant market substitute for the protected aspects of the originals."

If you think that gen AI doesn't provide a significant market substitute for the artwork created by the artists and authors used to train these models, or that it doesn't adversely impact their rights, then you're utterly delusional.