Really? I didn't expect this level of disapproval, TBH. New Zealand is a sovereign country - they can refuse entry to anyone they choose, for any reason they choose. And New Zealand's health care system isn't "****ed" - it's comparable to our own here in Aus (i.e. primarily taxpayer funded) which, while not the best in the world, is pretty OK by most metrics. The decision was to disallow entry based on a likely future burden on the health system, and, FYI, these decisions are made all the time. It makes news here every few years when someone prominent (usually a doctor) is refused permanent residency in Australia because of health issues (often in members of the family), but I'm sure it happens far, far more often for less "valuably employed" migrants.
Immigration departments have to weigh the value and the costs of every decision they make. They're not always right, but the system exists for a reason. Remember that nobody has the inalienable right to live anywhere they're not a citizen.