From my memory the GULAG was abolished, because it was not economical. The prison guards cost much more than the inmates produced and were corrupt as a rule. Yet, for decades, we can read about the rising US prison population and measures similar to the GULAG being tried, that is, using prisoners as a source of cheap labor. Why did the US prison system not implode similarly as the GULAG system did, over the decades, due to unsustainable costs?
EDIT: Here is the quote from my memory:
In reality, a consistent theme throughout the Gulag archives is that the Gulag system cost more than it produced and that it was creating a class of professional criminals.
From the common sense perspective, the GULAG was destroying its workforce (prisoners) and hence can be regarded as uneconomical simply because of that, but the US system is not much better, a jailed intellectual doing menial work can be viewed as a wasted resource as well. The same goes for jailed young people who cannot develop professionally as a consequence of incarceration.