I’ve known people that were getting too-young puppies, and explained this to them. They say “Oh, we handle them all the time...they’re socialized.” Wrong. Socialization isn’t about them thinking they’re people; it’s about being hardwired to be a pack animal, so that when their pack becomes people (and cats) they can function within it. The thing about six to seven week old puppies is that that’s when their brains and their bodies are ready to accept what is best described as empathy. One of the most important things they learn is that they can bite, which is necessary for survival. Another thing they learn is that they can also be bitten, and their behavior needs to be modified to minimize it.
I get the puppie socialization thing, but puppies and adult dogs can also learn socialization with people, depending on how they are treated. I love dogs in general more than most humans.