People get annoyed at insurers who will deny treatment but most of the time you can just pay it yourself. The government has decided that everyone should pay for health insurance but you'll never be denied care if you pay for it yourself.
So if you think you do require some care, just ask the medical practice whether they accept self-pay and then you can decide if it's worth paying or not. If you think it's not, it's unlikely someone else will if they have to pay on your behalf.
Essentially, place yourself in the role of each participant:
- patient: wants to maximize care, money no object since it isn't theirs
- medical practice: wants to maximize money spent on care
- insurer: wants to minimize money spent on care
Normally, the first two would be happy to collude to charge the third any amount of money since they'd both get what they want. And that is indeed what happens. So you get the natural result that the insurer doesn't want to support certain payments even if they were kind and pure-hearted. That they don't want to when they're neither should then not be a surprise.
You can remove that pressure by turning the interaction into:
- patient: wants to maximize care with minimized cost
- practice: wants to minimize care with maximized cost
The pressures between the two parties are now opposite and you can find the market equilibrium. With this opposition you'll suddenly find that patients start complaining about doctors ordering unnecessary procedures and so on, just like insurers claim in the other model.
You can also work through with the other versions to model where equilibrium will set in and see if it's where it does. Most of the time you don't need to assume any moral valence for the participants. They might as well be machines. It is their roles that determine how they act, not their personalities.