The insurer pays for it by not having to cover the expense of treating the disease anymore. It's an incredibly expensive disease to manage as a chronic condition. People who have sickle cell are going to have to have budgeted money to cough up their yearly deductible in any case. (Skipping out on paying medical bills is also a possibility)
And yes, I agree that not everybody will get treatment quickly because of the high cost.
Yes, older ones don't have tracking or user agreements which give the car company the right to record audio of your teens having sex. But that's not a long-term solution.