I'm not sure Nixoncare would actually be all that good as policy. I mean, look at all the public uproar over Obamacare, and yes, public support is a big part of successful policy.
Obama made at least 4 crucial mistakes, one of which I doubt Nixon would have and it was the most important one.
1)The most important one is that it was passed on an entirely partisan basis. The Democrats didn't seriously try to get Republican votes until it was far too late.
They should have had them in the room when the law was being made. Without Republican support, no mistakes would ever be fixed. The Republican had ZERO skin in the game so they had no reason to want it fixed. Any success would be given to the Democratic Party as well as any failure. There was no reason for them to want to succeed and every reason to want it to fail.
2) They set the penalty way too low. A young healthy person had zero incentive to buy Obamacare. They were grossly overcharged and the penalty was far lower than the premium. About the only young people who bought Obamacare are those who are heavily subsidized. The ones who have to pay full freight mostly avoided it like the plague and paid the penalty. Young people are exactly the ones you want in. They pay in and don't take out.
3) It allowed those under 26 to opt-out and be covered by their parents' insurance. Again these are the ones you want paying in. A lot of 18-26-year-olds, the ones you want in the most, got covered by their parents' insurance.
4) Because of this Obamacare tends to be HMOs with extremely narrow networks. Most people consider Obamacare to be "garbage insurance" as a result. This tends to make people want to avoid it because they don't get much more than being a charity case in the hospital.
2-4 will never be fixed because of 1. With no incentive to fix the problems and every incentive not to the Republicans will not vote for anything to fix it.
