“insuring” a pre-existing condition isn’t insurance.
“Hello, Allstate? Yeah, my house is burning down right now, can I get some insurance?”
The idea of insuring health was originally to level the costs associated with the possibility of the onset of a serious health issue.
It has since morphed into a quasi-discount pre-paid medical care plan.
You’re right, “insuring” a pre-existing condition isn’t insurance. It’s continuance of treatment. But at some point prior to the onset of the condition, it was insurance.