A superpower which doesn't exist any more, it was torn apart by its own lack of productivity and internal contradictions.

The industrialisation went quickly, true, but heavy industry was the only thing the Soviet Union ever got remotely good at, its state apparatus failed to incorporate advances made elsewhere, heck it was so bad that the GDR started its own chip programme because the Soviets wouldn't and they needed chips to stay competitive in the market of industrial machinery. Did you know that in the 80s VW Wolfsburg was full of GDR-built machines? They used the proceeds to buy things that are necessary to keep Prussians happy and not rebelling, such as coffee (I'm being absolutely serious here coffee was a big political issue in the GDR).

Meanwhile, rapid increases in lifespans and living standards aren't exactly rare because it's not actually that hard to get half-way decent when you start from a point of utter destitution.

The USSR did achieve nothing special in that regard, and definitely nothing special enough to justify the abuses that come with their approach.