At the same time I think a lot of people from countries where you really have areas you avoid as a citizen (say, the US) often get the wrong impression when they read about so-called "no go" areas. There's no area on this list that I would avoid going to. And I've been to many, many of them, and have friends/family living in many of them (nearly all violence is between criminals).
Again, not saying it's not a problem. It's a big problem. The police were given more resources in the latest gov't budget to deal with exactly this and will surely get more next year and it'll surely be an important topic in the 2018 election. We'll see how it goes.
What are some other things you think have quickly deteriorated? I'm interested in this outsider perspective.