I heard an interesting insight from the late rabbi of Aish HaTorah. In trying to provide a concrete understandable definition of "decadent" he shared the following definition: Any society that conflates the opposite of pain as "pleasure" is decadent.

It is a society that wants the pleasure of companionship (marriage) but at the first sign of pain, chooses divorce.

It is a society that wants the pleasure of children, but when that reality entails the pains of parenthood, they prefer to go without, or simply limit the number of children to minimize the "pain."

Ultimately it is a society that wants the pleasure of freedom but when faced with the necessity of paying with pain to defend it, chooses not to.