I agree with this, but I don't think people show up to interviews with sagging pants (hope not). It's the casual/non-working attire that's being dictated. By the same token, we should ban people who wear their collar up, sun glasses in doors, tank top in public (should only be used as undershirts), and a long sleeve shirt under short sleeve shirts because those are just tacky as well.
I think we should have a law against making laws for a while. Maybe create a maximum number of laws for any government. Then when they want to come up with something like this, they've got to figure out what is worth repealing to get it.