More people have health insurance, not health care. There is a very important difference.
The ACA, in any of its forms (which, it should be noted, what we got is radically different from what was proposed, thanks to people with a vested interest in seeing it fail), while a good step in the right direction on a lot of matters, didn’t and doesn’t really address the underlying issues that cause our failing overall health — things like lack of personal financial and food education, and lack of money for higher quality food, as well as poor, scientifically-unfounded governmental dietary recommendations that date back 3/4 of a century.
The US healthcare system is not about keeping people healthy, it’s about medicating illness (be it chronic or acute). A number of political interests keep the medical field in the Dark Ages on a lot of fronts. Sure, we’ve got antibiotics now. We’ve got some of the top surgeons and high-level specialists in the world. Yet things like the dietary recommendations for Diabetics (for example) not only keep them sick, but also make them worse, and despite scientific evidence that points to other ways, even nutritionists and doctors that support those other ways have their hands tied by either legal or cultural binds. General practitioner doctor visits feel like a joke, where you spend an hour or two just to get 5 minutes with a doctor who’s too rushed (because the US health insurance system requires they “see” a certain number of patients just to not lose money) to really listen to you or actually do anything if the reason you’re there isn’t something simple like Strep throat, where they can write you a prescription and send you on your way.
Outside of the medical field, there’s also the issue that the costs of a doctor visit aren’t just in the copays and premiums. Labor laws are such that it’s possible to be fired for taking time off to see a doctor (in fact, it’s even possible to be fired for an emergency hospital stay). Even if you manage to keep your job, a large chunk of the population doesn’t get any kind of paid time off, so on top of the copay, the cost also includes the person’s hourly rate, times the length of time required, and they can’t afford to take time off of work or risk losing their job, so they come in sick and risk getting even more sick.
And let’s not get into the issues with the exploitation of things like patent law that creates monopolies and artificially jacks up the price on certain medications. Or archaic and/or entirely politically-motivated laws/regulations that keep safer, more effective medications from being sold in this country.