IMO most people would not consider healthcare affordability as a factor in where they want to live, or even a major factor in their quality of life. NYC (as one example) is famously expensive across the board for all types of insurance, healthcare, housing, food, etc. but still has hordes of people who want to live there.
As an aside - New York State did launch a universal healthcare program recently, and I believe Colorado has something in the works on that front too.
