But you avoided his entire second question.
Please read up on adverse selection and moral hazard. The world isn't puppies and rainbows. Sustainability is the most important thing for any market when it comes to helping the poor in the very long term.
A sustainable insurance market is also obtainable without genetic information. In fact, without any patient information at all. Information allows segmenting the population to allow for diverse premiums. Without any patient information the premium will just reflect the whole population risk.
We can argue if this system is fair or not (I don't like these discussion because they hinge on the definition of fair, which is silly); but your point is about economic feasibility, and it's quite feasible to have a health care system without digging up dirt on everyone.
And, as a libertarian, I have to admit that this country has one of the most inefficient health care systems in the world. The amount of money we spend for results that are worse than any other industrial country is obscene!
This assumes the only reason for not participating is lack of motivation to be healthy. What about those of us who don't want to voluntarily surrender our entire genetic code to an insurance company? And once most people have, how do you know that your future premiums won't be based on genetic markers for certain diseases?