@Keith ***********
The visa type has nothing to do with it. As I explained several posts above already.
Everyone living long time in Thailand is required to have a health insurance. Does not matter if Thai, ASEAN or western country.
This is not a third world country.
The only weak point at the moment is: they enforce the requirement only for one or two visa types.
Hence your misconceptions.
Hint: Immigration law is not the same as Visa rules. There is a 130 Paragraph law book about immigration.