The best answer I have for you is maybe/probably. Clearly the city would be better established if it hadn't gone through all of that, but that's true for every place in the world.

The population of Stalingrad was about 445k in 1939 according to the Census. The current population is 1.02 mil. The world population has increased about 3.5 times since then, the population of Volgograd between 2 and 2.5. The remaining population difference can easily be attributed to different developing countries.

The thing that made Stalingrad so important is the thing that makes it easy for Volgograd to prosper: rivers everywhere. Currently the Volgograd Oblast isn't doing bad when looked at in the scope of Russia (their currency's exchange rate is plummeting, so it makes comparison of how Russian places are doing now to what they could be doing hard) but it has a lot of infrastructure, a fair amount of production, the largest Hydro Electric station in all of Europe, and a comparatively high amount of agriculture.

Edit: The modern population difference can be partially explained with how much easier it is to commute now.