Obamacare is universal coverage because no one is denied coverage. If you dont make any money you can get subsidies to pay for it.
Medicaid is administered by private insurers paid for by the state. It's the largest growth in their market over the last 10 years.
Bernie has said multiple times that he wants to outlaw private health insurance.
Obamacare is not universal coverage, you are simply making up your own definition for things.
Medicaid is still funded by the government, even if they contract it out it is still a government funded program.
Bernie's plan does not ban supplemental insurance.