While Congress may regulate interstate commerce, it may not regulate intrastate commerce.All health insurance was intrastate prior to Obamacare.
Also, the Federal government cannot force someone to buy any product at the cost of their personal liberty.
If they think they can, it is time for a major reset in Washington DC by the people.
Actually, it still is ...
You cannot contract with a healthcare provider who is not licensed in your state. That is, if the provider operates in one state only [not yours], you cannot contract with it [the GOP wanted this restriction removed in Obamacare - but was shot down].
Obamacare-ites put forward the specious argument that if a national provider IS licensed in the 50 states, then it IS engaged in interstate commerce ...