It's interesting, though, because anyone who has ever owned a cat knows that they are only barely domesticated. It might be something in the canine brain that makes it easy to domesticate them.
Housecats also have a number of behaviors that seem only distantly related to things that would be useful in the wild, such as meowing for attention. Another weird behavior is when cats line up dead mice outside their owner's bedroom door like a present. There's clearly some relationship that they understand between themselves and their owner.
People seem to love them as semi wild animals and unlike dogs they aren't dangerous enough to be put down when they start biting people. On top of that a large percentage of the population are actually wild animals aka feral. Spend a lot of time with a kitten and it may become extremely affectionate, but we also habitually neuter them unlike the wild population. Go back 1,000 years and I suspect people acted similarly though without the neutering.
So the external evolutionary pressure for domestication doesn't seem nearly as strong as with those foxes, and might currently be going in the other direction.
just speculating, but wolves are "pack" animals, so they are already adapted to cooperating with each other and following a leader. perhaps that made them easier to train and domesticate. cats aren't like that except in the "lion pride" breeding sense which is perhaps a narrower skillset in terms of utility.
and of course, anybody who has owned a tiger will tell you that a cat is fairly domesticated :) I mention it because "domesticated" and "useful as a friend" might be two different things.
It's easy to imagine humans simply tolerating them because they kept mice under control around grain and other food storage.
Intuitively that matches my perception of the cat-human relationship vs. the dog-human relationship.
Edit: visibly dog lovers are not too keen on learning that their best friends have a genetic abnormality. But that doesn't make it less true, it's pretty well documented. It doesn't mean that dogs are lesser somehow, they are still perfectly viable it the wild (well not the races resulting from the most extreme genetic selections, but most of them)
There are plenty of other genetically similar canine species that aren't domesticated. There are plenty of related animal (seals, ferrets, skunks) that aren't been widely domesticated, but are completely capable of being domesticated on an individual level, and none of them possess genetic abnormalities
One thing that many of these animals have in common is that they are fairly comfortable and adaptable to living in very close proximity to humans. That's true of modern day coyotes, raccoons, etc.
Humans have 99.9% identical DNA. All the variation you see in humans is explained by just 0.1% genetic differences. There's no reason to believe that the same isn't true for dogs without having to resort to a rare genetic deformity.
It's more likely that the social phenotype that is present with many WS patients emerged in dogs due to evolutionary pressures (explicit and implicit breeding) than dogs emerging due to WS.