Joe Paduda has some interesting points:
“requiring insurers accept all applicants is favored by most Republicans (according to Politico) but a) some senior Republicans hate the idea and b) there’s zero consensus re how to actually make that work. Do they forbid upcharging for older/sicker people? Adopt some form of risk-adjustment and/or financial transfer among/between insurers based on the risk profile of their members? Or allow the free market to operate, hoping that insurers will somehow figure out how to insure people with pre-existing conditions at affordable rates?”
One option–an individual mandate–is certainly off the table for Republicans. So the question is, if you want to prohibit insurers for varying premiums based on your health condition, how do you prevent premiums from skyrocketing or insurers acting illegally to avoid certain types of enrollees. The answer to this question is not a simple one in the political realm.