Imagine OpenAI had invented a software program that turned any written text into an animated cartoon enacting the text. That would obviously be creating a derivative work and outside fair use bounds. That they mix a bunch of works (copyrighted and otherwise) into a piece of software doesn’t allow them to escape that basic analysis.
Google showed a “clip” of the original work, no different in scope than Siskel & Ebert showing a clip of a film as they reviewed it. The uses are not comparable.