The headline look pretty accurate to me. Under this ruling, being a US citizen does not guarantee you a constitutional right to safe drinking water; that right would depend on state legislation.
I think the bigger deal is that the people of Jackson were lied to and this sets the precedent that there is no recourse. It's not like someone in Flint knowingly drank contaminated water, the city withheld the fact that their water was contaminated with unsafe levels of lead.
There is another way to look at it.
As water consumer, I have a right not to trust officials about tap water quality, and buy my own drinking water in plastic bottles!
I use Jackson example, everytime someone pushes "tap water is safe" bs!
As the article says, the situation in Jackson was deplorable; and it is indeed mind-boggling (to my puny European mind) that the same constitution which grants freedom of speech and the press was also not intended to grant the right to receive only believed-correct information from the government. But the ruling, for example, is not quoted as making any mention of any federal laws? The headline may be true for all I know, but the article provides only evidence for its truth about one particular source of rights.