I wonder what a wild cow would act like.
And then I remember bison.
Less like bison, more like cape buffalo. Picture something two or three times the size of a modern cow. It has long, sharp horns. But the physical differences aren't the big ones. The behavioral ones are the important ones.
When a herd of cattle notice a threat, they move away, stampeding in the opposite direction. The ancestor of the cow, the aurochs, didn't have with that. They would stampede
toward the threat. And then very quickly make sure it wasn't a threat, ever again.
Julius Caesar spoke of these things with awe, and felt it would be impossible to domesticate them. The fact that people had done so, and done so so well that it was unimaginable that the cow and the aurochs were the same beast, is a testament to our ancestors' ingenuity.
As for cats, they are domesticated to a large extent. True wildcats don't stay in that extended kittenhood, no matter what you do with them. Cats simply aren't as domesticated as dogs, because their natural independence made them excellent for pest control.
The extended childhood (called neoteny) is a common feature of many domesticated animals, particularly cats and dogs (and the domesticated silver foxes). It's the most convenient way to use the animal's natural instincts to make it pliable.