The fact that people with mental illnesses are being locked in a prison cell in the U.K. simply because there are no hospital beds. A 16 year old kid who was very depressed and suicidal was put in a prison cell for committing no crime, just being born with a mental illness. ....and people are okay with this, how?
What is next ? electric shock therapy again? 
Basically the U.K. needs to have a massive protest and this unethical treatment but they probably will not. Because in reality nobody cares. Despite what it is said, the general public is embarrassed to discuss it when it is serious. They give evil looks at anyone suffering a public episode. It can be crying, panic attacks getting over-loaded with frustration and appearing angry. This seems to be ridiculed and nobody ever thinks about what it is like to live with that everyday.
In the end, it's just something that costs the world governments money.
Don't think you would find many people who are ok with that!
But what else could they do with no bed available and the young person needing to be detained under a mental health section.
Not ideal by anyone's standards, but at least he or she ( was it a young girl?) was safe and I understand that mental health nurses were caring for her in the police station.
Very difficult decisions are being made every day in an NHS which is in constant crisis. This is an extreme case and yes it is appealing.
Do agree with the second part of your post, maybe that is the British stiff upper lip coming to the fore........ I do think mental health is very low on the agenda and still a very taboo topic.
I work in an acute NHS hospital ( the one that is always on the news.....

) and we struggle to get any help for patients with acute mental health issues