So kids are worse in some 'X Y, Z', but in any of hundreds of statistics we collect they are better. Except the fact that younger generation has less sex, but that seems to run contrary to the spirit of the complaint.

Whats the difference between elusive 'X, Y Z' we can't define or measure, and 'X, Y, Z' that doesn't exist?

>So kids are worse in some 'X Y, Z', but in any of hundreds of statistics we collect they are better.

That's more of an argument that one can't really trust statistics. Or that they don't always measure what matters...

>Whats the difference between elusive 'X, Y Z' we can't define or measure, and 'X, Y, Z' that doesn't exist?

Well, we can define, and it does exist. Not sure if we can measure (not everything that exists can be measured in some meaningful way. Some things matter in qualitative ways).

So, for some concrete examples, the roman generations that followed the acme of Rome and steered it towards the decline had certain very specific characteristics. Less inclined to work for common good, more selfish, having less children (lamented by roman critics of the time, and which less to a big problem with economic dynamics, the army, and so on), more concerned with greed and self-indulgence, less interested in civic matters (which was the bread and butter of earlier generations), and so on.