I think we have the wrong equation. It isn't about kids being more disrespectful, it is about society being more disrespectful. Children are a reflection of the world around them. As adults get harsher, so do kids. You can't expect kids to behave better than the role models they see.
I'm actually pretty amazed at the good things I see from kids. They get exposed to so much that is negative, and yet they still yearn to do right. Gives you faith in human nature.
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Mom to an amazing young adult AS son, plus an also amazing non-AS daughter. Most likely part of the "Broader Autism Phenotype" (some traits).