As far as I know, there isn't a formal copyright-related US court ruling (yet anyway) of training ML/AIs on any media (except for copying the code of an ML). So

As far as I know, there isn't a formal copyright-related US court ruling (yet anyway) of training ML/AIs on any media (except for copying the code of an ML). So everything is actually on thin ice, much like the infamous "GIFs [from snippets of shows etc.] are widely believed to be fair use", which in reality is still untested. Let's not forget other countries, with much stricter copyright rules (especially moral rights).