On the other hand, if we were to ever move to New Zealand where I lived most of my life, or to the town in Poland where my son's mother grew up, this would be an entirely different story.
Anywhere in New Zealand is quite honestly Disneyland compared to the UK (and I am thinking of the 'hard' parts in New Zealand like Māngere or Ōtāhuhu)... and Radomsko in Poland still has some nice forest areas and a lake that is walking distance from the town.
I think the author needs to take into account that there are just some places in the world where you must be on guard and be extra vigilant. This isn't limited to London, for example Cape Town in South Africa or Rio de Janeiro in Brazil spring to mind.
I am however very much aware of the impact my decision to keep my family in London will have on my son's childhood and frankly I would rather move outside of the M25, to say the outer edges of Surrey, where I would feel slightly more at ease but still ever vigilant. Until I can afford to do that, holidays to Poland will have to suffice.