[kelseyfrog]

Right, and some physicists have a nagging feeling that the addition of another symmetry would result in the reduction in free parameters. "We've done it before, so why shouldn't it work again?" is their thought process. So they devise a model which replicates the standard model in observable ranges and to make it testable, doesn't replicate the standard model outside of the observable range. This is an attempt to make the model falsifiable and thus scientific. Then they advocate for expensive accelerators to falsify the model.