Look through a longer lens.
I think Obama will go down in history as the most ineffectual President in our history.
He'll go down in history as the first black man to be President.
That, first and foremost, is what he will be remembered for.
No-one will remember the fine detail of the ACA, just that happened, and that Obama made it happen. In the same way that few people nowadays can tell you the details of The New Deal, just that it happened and it was Roosevelt who made it happen.
Scholars of political history will note that he managed to get a certain amount of shit done, despite the full-blooded attempts of the most obstructive House and Senate ever.
And those scholars will observe that the ACA, despite its imperfections, extended health insurance to a metric shitload* of Americans who never had it before.
Things you have to remember about any large-scale changes to any large-scale system:
1. It will make someone worse off
2. Someone will game the changes
3. It'll cost a lot, and probably more than you'd expected or hoped
These are not reasons to not change.
