I recall some Roman writer complaining about the worthlessness of the youth and how Rome was doomed.

Just before a boom of conquest.

Moralising elders waxing nostaltic have probably been around longer than preserved writing.

Edit: it was Horace:

aetas parentum, peior avis, tulit nos nequiores, mox daturos progeniem vitiosiorem.

Our parents’ era, worse than their ancestors, bore us still worse, and soon we will give more wicked offspring.

Text and translation obtained via Wikisource: Horace, Odes 3.6, published 24 or 23 BCE, during the earlier years of the reign of Octavian Augustus.

We could argue about the quality of a youth that bowed to what would be a monarch in all but name, but it’s hard to deny their courage and effectiveness in battle, which would have been an important virtue in Rome at the time. That “wicked offspring” stabilised an Empire wracked by decades of civil war and unrest, expanded it and by Horace’s standards should have been quite honourable.

(Note: this is not an endorsement, just commentary on the mentalities of the time)