Would a neutral Norway change Italy's war?

Would a neutral Norway significantly affect Italy?

Not by itself; the major Italian consequences follow if Germany invades, loses badly, and Norway becomes an Allied operating base.

A neutral Norway alone does not obviously transform Italy's position. The larger effects emerge in the invasion-fails branch, where German naval losses and Scandinavian resources reshape the Mediterranean balance. In that branch surviving British ships can reinforce the carrier attack on Taranto and reduce the Italian fleet's freedom. The two counterfactual paths therefore remain distinct.