Question: if retirement plans that feature health coverage experience massive (unexpected) increases in health care insurance, can the retirees get dumped from private health care plans into Obamacare and an Obamacare plan, which then might (unexpectedly) charge the retiree, based on their retirement nest egg and pension?
Yes it’s possible, and frankly that is a long term goal of Obamacare - make it so expensive and complicated for private insurance companies so they are unable to compete with government-run non-profit exchanges. That’s the path to single-payer. Below is a link with an example: