The best way to reduce all the excess manufacturing for livestock is by not buying it their products.

has that ever worked?

here’s a sidechannel attack on your position: every use, even infringing uses, are fair use until adjudicated, because what fair use means is that a court has agreed that your infringing use is allowed. so of course ai training (broadly) is always fair use. but particular instances of ai training may be found to not be fair use, and so we can’t be sure that you are always going to be right (for the specific ai models that may come into question legally).