The Affordable Care Act is the biggest non tax cut legislation of the previous 30 years.
I would argue that the Affordable Care Act was nothing more then a common sense consumer protection legislation for a consumer market that should not exist in the first place.
The fact that it was this big and this hard to get and with this many compromises against consumer interest, speaks more of the disfunction of the USA government at the time then it does about the value of that legislation.
And to add to this, for also properly dealing with the 2008 financial crisis. Just as a reminder to those out there, the strategy of recent administrations for crises like this was to cut federal spending in order reduce deficits, and many of the politicians at the time were calling for cutting spending. Obama listened to his economic advisors who told him to stimulate the economy and get money into the hands of the people. There were some rough edges to their stimulus spending but it seems to have worked and our recovery was the envy of most of the world. In recessions, stimulus seems to have now become the norm.