The reality is, I think most people don't realize how hard others have it, and how non-trivial such things can be for those in more dire straits or those that are more destitute. These are simply not options for many folks. Where's the money to move, to relocate, the wherewithal? The sheer number of factors that tie people to less-than-ideal places can be daunting, and those not living in that kind of squalor are sometime oblivious...or lacking the empathy, to understand its rarely that simple.
In some cases there are going to be some extenuating circumstances that prevent things like moving. For instance, extreme disability is one possibility, though that does not seem to be the issue in this case. The mother seems able, younger mid aged, and had 3 children. If she was disabled in any significant way, the media pieces and her crowd funding would also have mentioned that, to further draw at pathos.
Ultimately you cannot discount the fact that there are many negligent parents. In this case the parent is claiming, in her crowd funding page [2], that she only realized pollution might be a trigger for her daughter's asthma, after she died. Quoting her, "Since her death I have become aware of the dangers posed by air pollution and discovered that our home, located approximately 25 metres from the South Circular in London, was a known air pollution ‘hot spot’ and started to put two and two together. ". It's insane and inexcusable that somebody can have a daughter with severe asthma and not realize pollution and fumes can trigger it. That's something any 10 second search on asthma would turn up.
[1] - https://fivethirtyeight.com/features/how-many-times-the-aver...
> It's easy to live outside of a heavily polluted area if you have severe asthma.
Most people can't just move, but it's easy to just move?
I am straining to maintain the notion of civility that HN demands, so I will only ask you this: what bent you to make you think this sort of thing is reasonable or okay or decent?