"The children now love luxury; they have bad manners, contempt for
authority; they show disrespect for elders and love chatter in place
of exercise. Children are now tyrants, not the servants of their
households. They no longer rise when elders enter the room. They
contradict their parents, chatter before company, gobble up dainties
at the table, cross their legs, and tyrannize their teachers.

- Socrates

The following regarding things have been neglected:
"I mean such things as these: ? when the young are to be silent before their elders; how they are to show respect to them by standing and making them sit; what honour is due to parents; what garments or shoes are to be worn; the mode of dressing the hair; deportment and manners in general. You would agree with me? ? Yes."

- Plato

"The world is passing through troublous times. The young people of
today think of nothing but themselves. They have no reverence for
parents or old age. They are impatient of all restraint. They talk as
if they knew everything, and what passes for wisdom with us is
foolishness with them. As for the girls, they are forward, immodest
and unladylike in speech, behavior and dress."

- Peter the Hermit (1274 AD).