It is certainly common enough for people to feed peanut butter to their four-legged companions that if Xylitol is found to be toxic to dogs, it should be banned. If it is an additive, it would yield safer outcomes to find an alternative solution to what it is adding to the product and keep dogs safer in the process.
It's the responsibility of the dog owner to know what they're feeding their dog. If you own a dog and don't read the label of every product you feed your dog, or know what foods are safe to feed your dog, then you shouldn't own one. Stop relying on other people to make sure you don't mess up and kill your dog.
No, Xylitol should not be banned. This is a product used in human food, and it is harmless to humans. It is important that the public is educated on Xylitol's effects on dogs, and labels should be required on products that contain this substance. However, companies should still be allowed to use it.
No, Xylitol should not be banned in any products, including commercial peanut butter brands. It should, however, be required by law to be clearly labeled as an ingredient, so that consumers can make smart choices for themselves and their pets. Long term studies should also be conducted to ensure that current science, which says it is safe for humans, is accurate.
We do not need to ban any peanut butter that contains Xylitol because it is toxic to dogs. Any credible vet will tell you to never give human food to dogs and to not consume food for dogs yourself obviously! Any good pet owner is more careful than that with what their pet eats.