For anyone who doesn't want to go through the Daily Mail here's a link to the original research paper - it's open access.
doi.org/10.1002/nau.25132
When grown adults are choosing this when there is plenty of information out there stating the high risk, they can do what they like.
Is there though? Where is it? Can I read it? Because everything I have read either uses medical jargon and needs a lot of medical background to understand or it's been so fucking coy .
If there's a consumer guide to this in everyday language then I would really love to know!
Presumably they are making an informed decision.
A million scam artists can tell you that being over 18 doesn't automatically make anyone fully informed and able to make a good decision.
There has to be a point where adults are allowed to make their own decisions, as long as they are fully informed of the risks.
Please point me at the "Which?" guide that fully informs everyone of the risks 
Recent WPATH World Professional Association for Transgender Health guidelines, which claim to be the international standard for trans healthcare, have been carefully written to (a) maximise the amount of surgery that (US) health insurance will pay for and (b) minimise risk of (US) doctors being sued and (c) do not contain a section on medical ethics.
gender-a-wider-lens.captivate.fm/episode/94-wpaths-bizarre-8th-standards-of-care