No one objects to universal access to health care. If you mean a system where there is one national health care and everyone is required to use it, including the politically well connected, that never existed anywhere, even in totally socialist systems such as the Soviet Union (somehow the rich and powerful get better care).
Obamacare is just an expensive set of options towards getting access to health care for those without (which was never a very significant number in the US). For political reasons, they banned many “deplorables” from using inexpensive health insurance (the “deplorables” answered back by electing Donald Trump).
Managed care is a type of health insurance that offers (in theory) lower prices in return for the insurer taking control of what care you are offered (one can negotiate the price and standards).