Retirement accounts are a real issue, but could be solved by having the top wealthiest shareholders pay out to the poorest shareholders until retirements are guaranteed. This could also be combined with Social Security reform that requires wealthy people to contribute more and extract less from the system.
Presumably many of the actual healthcare workers and some of the admin workers would still be needed in a nationalized system. The insurance agents and related admin can all get other jobs. No one dreams of being an insurance agent as a kid, these people would be free to pursue more meaningful and useful work.
None of these are insurmountable problems for a government that actually serves the people instead of money. This article is just prevarication to cover our current governments inaction.