Fantastic regarding the MSF donations! And as a woman, I agree we (women) tend to make less money. Did you know trans women (compared to cis men) have twice the pay gap as cis women do? Equal pay is a big deal for trans and cis women (one thing I believe we can and should work together to solve) and I'm always happy to see another feminist talk about that.
A nation like the USA or Canada has the resources to pay for medical care for the citizens - including trans care, child birth, drunk driver accidents, etc. If it doesn't, rather than arguing about which group shouldn't get medical care, we should be arguing about taxation, efficiencies (or lack of) in the medical system, and public policy in general (things like helmet laws for motorcyclists, proactive cancer screenings, improving food choice in poor communities, anti-smoking programs, workplace safety regulations, etc - all of these will save far more money than is spent on trans surgeries, not to mention saving a lot of human suffering).
As for comparing it to having children or drunk driving, I compared the choice of transitioning (I don't believe being trans is a choice, but I'll waive this point here) to the choice to have children (it's not always a choice, I recognize) and the choice to drink and drive that ends up resulting in injury. Obviously, like all similes and metaphors, some aspects of the comparison are similar and some things are different. (Childbirth and drunk driving injuries both cost the medical system money, for instance, and often result from someone's choice, but obviously are different in a lot of ways - and nobody, myself included, would argue otherwise; likewise with transition).
Let's say transitioning is a choice. Drinking at the bar and getting into the driver's seat of a car is a choice. A couple deciding to try to make a baby and bring that baby into the world is a choice (note I don't believe all pregnancy or child birth is a choice, but some of it clearly is). All of these acts have the potential to use a lot of medical resources. If we don't have enough money for current life and death medical care, it would seem to follow that someone who chose to have a baby would be taking resources from someone - maybe a cancer patient or someone who had a stroke. So they would perhaps be immoral to have a child. Don't worry, I don't believe that. I believe it's immoral for a wealthy country to ration medically necessary care, period. We have enough money to provide good care before, during, and after child birth. If we choose not to, it's not because the USA or Canada or whatever other wealthy nation doesn't have the resources. It's because they choose not to use the resources. Likewise for trans care - taking care of such a small percent of the population is insignificant in health care budgets, and the resources can be available - if the choice is made to provide them. The choice to use the resources doesn't involve preventing people from having children.
But since you noted the high amount of resources I used, we know that in the USA (land of outrageously expensive medical procedures), adding transgender care to insurance costs increases premiums approximately 0.016%. Viagra costs US insurance plans approximately 5X as much. Of course smoking costs health insurance hundreds of times as much. I'm not in favor of letting smokers die without medical care or even telling men their sex lives are over.
My point isn't that transition is like smoking, drinking, child birth, or Viagra. It's that if there is a problem with a health care system not having enough money, focusing on a tiny expense is probably the wrong approach.