In that video they show how far they still are from domesticated foxes compared to modern dogs. Well, domesticated pretty much means, "desirable traits for human benefit" when you think about it, the same applies to humans, but we call that civilized or sociable. Theres a joke in the comments, something like the fox goes "I'm okay with you being a meter away from me... but let's keep it that way." The dog, "you cant ignore my love!"
But I fully disagree on the assessment that larger dogs are more wild. Smaller dogs tend to be complete violent assholes for little to no reason. Larger dogs tend to need more reason to become aggressive, unless they came from an abusive environment. I volunteered at an animal shelter for about a year (admittedly to pick up women originally). But I gladly hung out with pits and shepherds from abused pasts so they can be rehabilitated for new homes. I could never do the same with anything smaller than a border collie. Just never worked out. Large working breed dogs are crazy easy for me to calm down, and I am generally not a brave man. Dogs have been bred the last 40k some odd years to genetically want to be with humans. Then some assholes the past few thousand years decided to breed for looks and tiny sizes instead of companionship. That's what makes the larger working dogs great. Listen to and love humans, and have a job to do is their breeding line. Not just looks, which can breed out the friendly part.
Caveat though, there are some pit lines that are a bit whack. Sadly, originally they were bred for fighting other dogs, but super strong friendliness for humans, to avoid the owner getting bit. Which is why they're cuddle bugs with people and are dicks to other dogs. This breed attracted a bunch of dipshits that bred them for just pure aggression, then add on the abuse. So yea... those are the sad cases.