The problem with most of these insurance bans is in the way they handle mixed breed dogs. They will require you to identify the mixed breed dog as a combination of two and only two breeds. They will not accept "shepherd mix" but they won't accept "shepherd/lab/chow/poodle/golden" either. Instead they require you to choose two of those breeds. So you choose "shepherd/lab" and everything is good. But if you choose "shepherd/chow", they say the dog is banned. It's the same dog with the same risk.
This is the biggest problem with breed bans. They are based on appearance and a simplified understanding of genetics.
My rescue group took in two sibling puppies. They were at least husky and shepherd. The male looked like a husky and acted like a shepherd. The female looked like a shepherd and acted like a husky. People saw the "shepherd" and expected a dog like their beloved shepherd - loyal, dedicated, eager to please. It was extremely difficult to get them to accept that she was not that shepherd. She was always thinking how to outsmart you, she got bored easily and found things to occupy her mind, and she didn't care if you liked it or not. I turned down many a home because they couldn't see past her appearance.
Genetics means that the puppies get half the dna from mama and half from papa. But each puppy gets those halves randomly. Add in that few dogs are just one or two breeds and that causes even more differences. So you can have three puppies from the same litter and all three will be different. One may have more chow appearance but more lab personality. Another may have more beagle looks and personality. And the third may have the coat of a lab, the shape of a beagle, the scenting instincts of a beagle, and the protectiveness of a chow. But they are all the same mix breed. Which do you ban? The standard is to ban by appearance - so you've banned the dog with the lab personality and accepted the dog with the chow protectiveness. Which is more likely to bite due to "breed"???