You're really not understanding this. That's got nothing to do with the insurance model. That's just a regulatory thing. All those choices do is change the s

You're really not understanding this. That's got nothing to do with the insurance model. That's just a regulatory thing. All those choices do is change the specific population that gets insured in a single pool, such that their specific computed premiums are different. But for ANY such population, the total premiums paid == the total loss outflow + a reasonable profit. And you can tell that's true because the accounting for those companies appears in their SEC filings. In practice, car insurers are allowed to partition their customers this way because it's felt to be "fair" and because it encourages safe driving. Trying to partition health insurance customers like that feels "unfair", and has minimal net benefit as health expenses aren't as controllable-by-the-subscriber as car accidents are. So we pass laws about how the partitioning gets done. But again, "insurance" as a business model (and mathematical model) works EXACTLY THE SAME WAY. The only difference is how you draw the lines around who gets insured at what rate.