Note that the point was not to criticise Pakistan - it seems like they are putting in quite an effort to modernise the systems. It's just that lot of these things look better on the surface and so are easy to underestimate the seriousness of the challenges.
E.g. if you have a well or running water, and no alternative, you use it, because no water is far worse than bad water. And most of the time chances are it'll be ok.
That makes it easy to conclude that it's probably safe even when there are flaws in the supply that can quickly render it unsafe or that makes it unsafe for sustained consumption.
E.g. arsenic leaking into the supply won't kill you from a drink here and there - arsenic is difficult to kill with, because too high concentrations makes you puke it up - but sustained ingestion of smaller doses may have severe and lasting health effect and may ultimately kill you.
(Arsenic is "interesting" in that a lot of arsenic contaminated water from pumped wells in developing countries is a result of inadequate testing in the rush of upgrading water sources from surface sources prone to bacterial contamination - as such, a lot of those pumped sources may in fact still represent an improvement, but in some cases also still represents a severe health risk)
Overall there's a great deal of progress in securing basic safe water supply. We're just not there yet. Even many developed countries regularly run into water supply issues.