Seriously you really think people who don't have dogs, or even a lot who do are interested enough to actually learn this stuff? Loads and loads of people get dogs for company or as a toy and have no intention of thinking about their needs as an animal or the appropriateness of their environment for a dog.
Why is it society's responsibility to make sure children can understand stress signals from dogs that people insist on bringing around children? Surely children are not even going to be able to actually do this well anyway and parents cannot watch them all the time, plenty of parents won't be able to do this well. In our local children's park there is a leash law, dogs are banned from the playground, about 1% of owners use a leash, everyone else argues their dog needs the exercise of running around, every year the protected wildlife that lives in the park is disturbed and/or killed by dogs, children and adults get dog shit all over their shoes and clothes, these people choose not to let their dogs off the leash in the dog park which is actually round the block a few hundred metres from the park, they do not understand it is their responsibility not to have a dog if they can't own it responsibly.
Why do dog owners not have to take responsibility for their dogs? Keep them in dog friendly conditions or not at all and don't take them to parks and round town and on the school run or any other place a dog will need to be actively controlled and will feel stressed out?
Some dog owners are responsible, many think they are when they aren't and some don't actually care. I've always taught my children to be wary of dogs and not approach them but as others describe it has become virtually impossible to go anywhere without being accosted by a legion of completely irresponsible dog owners who bring dogs into the playground because "I know when my dog wees and poos" let them run wild because "he is a big softy" bring them everywhere they go even if it is totally inappropriate because "ooo she is my baby" or keep them in totally inappropriate places because "I can't help where I live".