Don't you have that the other way around? If you want profit, you'd want a bunch of healthy people paying you premiums. Critically ill patients are expensive, and if they die, they won't be paying premiums anymore.

Auto insurance companies want safe drivers who will never ding their car and continue paying a low but steady premium, not reckless drivers who wreck their car every month.

From an insurance company perspective, preventative care might make sense, but if premiums were lower as a result, it might be counter-productive.

I'm sure there's a Nash Equilibrium here where people need to be "optimally sick" and this is a point some distance from "perfectly healthy".