Because of price fixing among the 3 big insulin providers, which is only possible in an environment where competition is heavily constrained by monopoly powers

Because of price fixing among the 3 big insulin providers, which is only possible in an environment where competition is heavily constrained by monopoly powers (or in this case, oligopoly powers) endowed by governments through the patent system. If we have an international free market that encourages 10+ competitors that aren't banned from producing insulin due to patents, then price fixing becomes impossible. So if government just got out of the way (in this case - patents and banning imports), you could import cheap insulin from anywhere and the problem would be completely solved.