The growth was staggering because they stole grain and farmland from their citizens, exported it to buy machinery because the USSR couldn't manufacture themselves, which was also wasted since they didn't have the ability to keep the machines maintained properly.
So yeah, turns out you can do things if you starve your people to death. (See North Korea)
They industrialized fast enough to defeat the Nazis who otherwise would probably have exterminated them. The urgency and the threat they faced if they didnt industrialize quickly enough was real and existential.
And yes, in order to do so they caused millions of Ukrainians to starve by exporting all of the food they grew.
Exactly like Britain did to my ancestors in Ireland for profit.
So yeah, turns out you can do things if you starve your people to death. (See North Korea)