Gulags don't exist during communist times.
Famine do not exist either - neither do massive shortages in simple daily materials - all of that cannot exist in the communist utopia, because otherwise the communist utopia would not be an utopia, wouldn't it?
As for no-go zones - the matter is not that you cannot walk through there or even live there. The matter is that postal services, courier companies, police officers, emergency services, firemen, blonde lone women, occasionally even too european looking men - all those get attacked and harrassed. Cars get burned once or multiple times a year - mostly cheap cars that the local poor inhabitants used, so they are left poorer.
We have currently effective nogo zones in Sweden, France and Germany is getting there.
A nogo zone does not automatically mean that you get killed and robbed there or that you may not even be able to live there especially if you look muslim or black enough. However it's essentially comparable to a very very bad black neighborhood - good luck living there while not being black. The crime rate may be even higher in the black neighborhood, but at least they are not stupid enough to attack firemen and emergency services, fedex still delivers there. It's a different kind of area where the local mostly muslims essentially create their own little fiefdom with as much as they can get away with - all without risking the implementation of huge police teams and mass arrests. So it usually resorts to attacks and violent harrassment.
Though - no country should tolerate that - any sane system would kick all of them out, offer them money for their citizenships and then give them a lifelong entry ban for all of Europe. That is what supposedly gulf countries are doing and I see nothing wrong with it. Only that gulf countries are not stupid enough to give every mohammed a citizenship - regardless whether he is there for 5, 10 years or is even born in Dubai. Plenty of Indians are born and raised in Dubai, but will never be a local citizen.
en.wikipedia.org
