I'm not sure if the female attorneys I work with who have dealt with old men calling them "honey" and"sweetie," and referring to them as "girls" would agree that younger generations have worse manners than older generations.
Morals and manners are a matter of perspective. I consider a lot of things that some people decry as PC with respect to treating people with respect, not being creepy with women, etc. to be good for society. And that all goes to manners and morals. Ironically, a lot of people who complain about being too PC are also quick to complain that society just isn't as polite as it used to be.