Seconding what Don M said. My in-laws live in Canada, and they find it appalling not only what Americans spend on healthcare, but how so many have NO health coverage at all, leading to more severe illnesses/disabilities because of lack of preventive care. And also the inadequacy of our social services safety net, which contributes to the US's very poor standings in average lifespan. We are ranked so far down we are in company with Third World countries, in fact.
We have over 200 relatives in my spouse's extended family. Not one has ever set foot in the US for healthcare.
Another separate issue: because most hospitals are for-profit chains, they are closing unprofitable hospitals and associated clinics in rural areas and smaller cities, at a rapid rate. Seniors should not assume that moving to a LCOL area will benefit them, because if it takes you hours to get to emergency or access a specialist, that may end up offsetting a low rent or modest property taxes.