The article focuses a bit too much on the city and not enough on the civilization that it was a part of. I guess the fact that it's in the Lost Civilizations series is an indicator? Anyway, for those not in the know – the city at Mohenjodaro is part of the rather extensive Indus Valley/Harappan Civilization that was contemporary with the Egyptian and Mesopotamian civilizations (~3000BC onwards). The reasons for its d…
> The reasons for its decline aren't particularly well understood. another victim of the bronze age collapse that we can't explain fully.
As far as I have seen, this is the best plausible explanation for the collapse - so far.