https://en.wikipedia.org/wiki/Monopsony#Welfare_implications explains it pretty clearly for the example of labor.
Or if you want to use the model, the deadweight loss in your evaluation can instead be interpreted as the price that people are willing to pay for the good feelings of knowing that everyone in the country has accessible and affordable basic health care.
Sure, but in the case of drug prices in countries with national health systems we don't really have any reason to think that the model doesn't reflect reality.
> the deadweight loss in your evaluation can instead be interpreted
Yes, this is exactly my point! The science of economics makes no judgement about the relative moral values at play here. That may very well be a tradeoff people want to make. Or it might not. Economics doesn't comment on that question one way or another, it nearly provides data on the practical outcome of the decision.
Companies unlike people should be allowed to die. That's one of the ways market evolves. One of the way market avoids local optima. Companies dying because they cannot provide the market at the prices market expects is the normal thing.
People dying because cartel prices essential good above what consumers can afford is not.
"They do so of their own volition". No. You are expressing the Panglossian viewpoint that just because something happened it was the best choice.
We know from experimental economics that people make decisions different than rational market theory would predict. The heads of large pharmaceutical companies are not exempt from this irrationality.
Nor are all people in government short-sighted pennypinchers. The price negotiations also include the reality that some of the profits are turned into more research for future drugs. Hence the questions of what "efficient" and "abuse" means, which go into the pricing negotiations.