The sourcing there is weak and questionable at best. That people assert that areas are "no-go" is pretty different than there being a genuine lack of any sense of order, and that's even before one looks at the issue of whether this is any different from some areas simply being higher in crime than others.
I am not making claims about "any sense of order", but going by what I read European police lost control of some chunks of its territory.
Take Calais. Here is a sympathetic account which is actually a kinda-detective story: a body in a wetsuit washes up on Norway's shore and people are trying to figure out who-what-why. The clues lead to an immigrant camp in Calais and, well, it's pretty clear that the French state lost control there.
Another month, another rationality quotes thread. The rules are: