The US healthcare system will evolve slowly as no country has ever moved to true universal healthcare in the face of many of the world's richest corporations.

A huge one is that it's very hard to move the needle on anything relating to the US healthcare system when a number of Global 500 companies are dependent on things being the way they are. CVS, Walgreens, Express Scripts, UnitedHealthcare, and Cardinal Health are all among the world's largest firms and all are resistant to change. Pretty much every major health insurer in the US, even if it doesn't do any business overseas, is a Global 500 firm, as are many drugstore, hospital, and pharma conglomerates. Any change to the US healthcare system is going to be glacial; no country has ever transitioned to a lower-cost universal-healthcare system when a big chunk of the global economy depends on them.