Most of the Affordable Care Act has nothing to do with the web site. The site didn't have to implement those "2.8 million words of Obamacare regulations" as code: it only had to match patients up with insurance plans, which means interacting with dozens (hundreds?) of government and industry databases.
Some states, like California, managed to implement their sites without any of the problems of the federal exchange. The federal exchange mainly suffered from (1) being rushed, and (2) having to deal with a larger number of external systems than any single state exchange.