I am genuinely interested in how much a 15 year old who decides they are gender dysphoric, might cost the NHS.
Lifetime hormones from age 16. Surgery. The cost of medical issues caused by the long term use of hormones. I assume it is massive. I am old enough now to understand how important it is to build the foundations of good health when you are young. Coming up to retirement age, and some people I know are already "old". Drinking, smoking, HIV, teenage anorexia, party drugs, obesity, occupational health problems, have caught up with some of my peers. It may not seem important when you are young, and even people of Susie Green's age may not fully understand, but the difference between looking forward to two decades of active retirement, or struggling with health issues, is huge.
Someone posted a link, either here or on Twitter a few months back, to an American transexual, the first transexual member of a californian policeforce, giving a talk. Not unlike some of the older transexuals in the UK there were clear warnings about gender reasignment not being something to be undertaken lightly, in particular because of the longer-term health implications. I have not been able to find the link again. A pity as it was both honest and shocking. The brave and stunning stuff is OK when you are young, but no one really seems to be looking at the longer term implications, perhaps by researching the experiences of the first generation of transexuals.