Article 370 doesn't threaten livelihood of Pakistanis. Infact India can make 1000 more changes to their constitution.
Geography and ground realities make India diverting water from 3 western rivers very difficult and expensive. Nuclear fallout insure India doesn't try to use water as weapon even if they could.
India have full right on 3 eastern rivers, these have 20% of water. 3 western rivers have 80% of water. India doesn't give Pakistan more share out of good will, they just have no control over it. Pakistan doesn't even allow India to build storage dams on western rivers. All dams must be run of river dams with minimum storage to generate electricity.
Majority of indus river water comes from with in Pakistan border glaciers. And water that comes from IoK they cannot control it.
Hindu terrorists on PDF and elsewhere want to use water as weapon as majority of them live in mahabhrat delusions.
These are few reasons Pakistanis don't care about Indians crying about Indus treaty.