It's really much simpler than a lot of the circle jerking going on in this thread.
Should health insurance companies be able to discriminate based on pre-existing conditions? If yes, continue pass go and develop your ideal capitalistic healthcare system.
If no, then you must develop single payer healthcare.
Not allowing insurance companies to risk stratify the people they insure (literally the foundational business model of any insurance company) ensures they provide little to no value but increase costs. You will have the worst of both systems. Which is what we have. Worse healthcare than most first world countries yet we pay twice as much per capita.
The majority of the voting public wants pre existing conditions covered. That's your answer.