Are Cat's Smarter Than Babies?

I've been thinking, why can't human babies evolve into being born potty trained? This does not seem unreasonable to me. First of all, cats are born instinctually knowing where to go to the restroom. Cat's don't wear diapers, do they? No, because they know what to do already. I've never had a kitten that was confused about it's catbox. Henry Lee knew it was for him immediately. So did Kitty XL. They also know they can go outside and that is the best option because mommy doesn't like litter boxes. XL only has a catbox for emergency purposes (in case he gets stuck inside too long), and he knows it. Sometimes he asks to go outside just to pee and come right back in. Good cat! So, why does it take babies so long? Clearly I'm having anxiety about the lovely task of diaper changing, which I've never had to do - ever. But seriously, is this too much to ask at this point in our civilization?