If your government-run healthcare service is being squeezed to the point that any important surgery is being deliberately withheld or heavily suppressed (whether it's a fracture repair for somebody who's just had a car accident, or sexual reassignment surgery for somebody at the end of a 12-month waiting list), something is very wrong. Your health service shouldn't have to focus on keeping people alive and nothing else; that kind of thinking is generally to be reserved for temporary crisis situations like major natural disasters. Obviously it's true critical life-threatening procedures are always given priority, but it's also true that resources will always be made available for non-critical non-life-threatening procedures (since they represent the overwhelming majority of medical procedures, and many of them prevent patients from becoming critical).

for every surgeon that specializes in gender reassignment we have a specialist who doesn't specialize in cardiac surgery, or oncology, or transplant surgery, or pediatric acute care

As I understand it, surgeons' specialties are mostly driven by demand. If the government were to try to impose particular specialties on surgeons, they would shed rather a lot of surgeons with other interests into private healthcare.

there is an economics of scale in treating those dozens in lieu of treating the few

I'm not aware of many economies of scale in human surgery. I would expect the cost of the same procedure, performed in the same way, to be quite stable. Surgery consumes a huge amount of expensive raw materials and infrastructure, and the surgeon herself represents only a small fraction of that.

I believe that the focus of this should be on attempting to prevent acute deaths and performing critical transplant surgeries, directly not indirectly saving lives, as opposed to improving the quality of life for a very slim minority of the population

If it's only a "slim minority" of the population who are affected, then the total costs will be correspondingly slim, won't they? I've had a kidney procedure which is only required by a "slim minority" of the population, because my kidney was giving me chronic pain - should that have been withheld, too?