Google Books is transformative in its use and for what it is, sure; and yet, if you do a query on Google Books and try to take the output and paste it into your

Google Books is transformative in its use and for what it is, sure; and yet, if you do a query on Google Books and try to take the output and paste it into your book, that might not be fair use (and I only say "might not" instead of "would not" as maybe you are writing a research paper and wanted a quote from a book or whatever, but of course that's just a silly corner case someone would try to call me out for on an Internet forum). Just because Copilot might be itself a transformative work which is itself allowed to exist, that doesn't at all necessitate a conclusion that the developers who are using it are going to or should somehow be guaranteed not be committing their own copyright sins if they try to incorporate its output into their own works (any more so than one can or should assume all of the outputs of another human being are free of copyright entanglements, even though no one is as-yet claiming a human being is themselves infringement just because they saw another work).