> Hitler lost sight of his material goal and instead fastened on one of only symbolic importance - Stalingrad.

This is oversimplified. Stalingrad was of enormous military importance in securing the advance into the Caucasus, it was relatively starved of resources and reinforcements for nearly the entire battle, and the degree to which its symbolism factored into decision-making is massively overstated and indirect.

The idea that Hitler (or Stalin, for that matter) had an overriding primarily symbolic obsession with Stalingrad is substantially just popular myth.