In reality, no one in the government have any serious plan of invading Pakistan occupied Kashmir. The main reason prime minister Nehru stopped 1948 Indian military campaign in J&K was due to the fact the territory under Pakistan control is economically worthless. Entire valley and popular settlements are under Indian control and that's when he stopped the war. 90% Pakistan admistated kashmir is constituted of Gilgit& Baltistan, a mountainous region with just 1.3 million population. It have like 50 mountains higher than 23,000 feet alone. Taking such a mountainous terrain is a Military nightmare, and not very practical. Taking Islamabad is far more easier.
While economically it's insignificant, it does have strategic importance. Cutting off Pakistan from China, and opening up a border with Afghanistan and further to central Asia.