News Corp fought Google mostly on their home territory of Australia, a battle which ended up with Google caving when News Corp succeeded in lobbying to get the law changed to be unambiguously in their in their favour (a battle AI providers should expect to face; the US isn't the only jurisdiction that's significant to them and legislation is bound to be updated for new tech). In France they got slapped with a fine of half a billion euros by an anti-trust court for not abiding by a French court order to agree fair license fees for news excerpts, and the EU's Copyright Article 13 is specifically designed to make platforms like Google News subject to EU-wide copyright law.

Google Images thumbnails were ruled infringing by one US court and overturned by another some time ago. More recently, the US also is the venue where Robin Thicke and Pharrell Williams ended up paying the Gaye estate royalties and naming Marvin Gaye a writer because Blurred Lines was apparently the result of Thicke saying he wanted to write a song that sounded like Got To Give It Up, and Williams using his knowledge of songcraft and what was distinctive about Got To Give It Up's groove to compose an original song with different words, note patterns and beat which nevertheless sounded similar, so I'm not sure there's much grounds for the absolute confidence most HNers seems to have that fair use defences will prevail in the US because of novelty and "learning".

Copyright law rulings are all over the place, and I think it's quite likely creators of such tools will be ruled infringing by one court and overruled by another, infringing in one region and OK in another, one diffusion model ruled non-infringing and another more commercially-oriented one ruled infringing, and perhaps others where either the creators or the users of the tool are deemed infringing but not necessarily both.