The bill, as written, was designed to force states to do the federal government's bidding - namely expand Medicare and establish state-run exchanges... Failure to do either would result in the loss of ALL federal Medicare funding or the state's citizens would lose access to federal subsidies (respectively).
This was not a case of poor word choices or an in artful choice of words, this was discussed and debated before the bill passed.
Once passed, both measures were challenged in court, all the way up to the Supreme Court. After fighting to keep the all or nothing position on Medicare, the federal government lost and had to fund Medicare in states that did not expand Medicare. And in today's decision, the government argued their much-discussed threat to the state's was really a typo.
These were calculated risks to force the state's to act in certain ways, both failed in their mission.