I wouldn't describe TTT's post as nasty so much as frustrating. I think it's worth accepting that some people just don't get this issue, and frame the question in terms of their own experiences -- hence, for example, regarding this as a "choice", which it is not. From such a position I suppose it's natural to pose such a question -- "why should the NHS fund lifestyle choices?" -- because they're starting from a false premise.
The best I can do is again stress that this is not a choice, or decision, in the sense that you are using it. People in such a position feel an almost irresistible compulsion, and are invariably less mentally healthy as long as they try to resist it. Anyone who did do this on a whim would struggle to last long.
Both the mental and physical aspects of transgender health deserve far more attention and far more respect than they are being given here.