And why would you think that the greater the population, the less likely a universal healthcare system would work?
I think the reverse might be true. The greater the population, the greater the problems of NOT having all citizens’ healthcare needs taken care of becomes. The greater the problem of uncompensated ER care becomes. The greater the problem of people not being able to be productive due to their healthcare needs not being met becomes. And the greater a burden on society due to an expensive and inefficient system becomes.