Yes, it is an exaggeration while in the case of Germany it’s literal (though in Spain, a few towns were razed, and many were heavily shelled)

People eating cats and rats off the streets is not an exaggeration however - there is abundant oral testimony to support that.

The point is that the damage hardly justifies talking about economies who live off inherited wealth, in either case.

There is an old saying in Spain meaning "they scammed you": Te han dado gato por libre (They gave you cat -meal- as hare). So, yes. after the civil war and Francoist repression Spain was utterly crushed down.

The use of that expression goes back several centuries, it has nothing to do with the war.