Rule reminder
'Non tanto perché X, quanto perché Y' means 'not so much because X, but rather because Y.' It weighs two causes, downplaying X and emphasizing Y. Variations: 'non perché X, ma perché Y' (simple contrast); 'non solo perché X, ma anche perché Y' (additive). These structures signal sophisticated reasoning.
What does 'non tanto perché' signal in a sentence?