Everyone knows Pakistan supported kahlistan not out of heart but-
1]Buffer between India and pak.
2]Isolate kashmir and stretch indian army .
3]Disrupt india's bread basket.
4]Create hatred within india.
5]Revenge for bangladesh
6]And lastly despite excellent agriculture,the area would be less developed in heavy industry[jharkhand/bihar and maharastra],and R&D centres[south] needed for large modern army-and be dependant on pak ,which would try to use it as a vassal.
And if an oppurtune moment arises try to annex it and unite it with pak punjab which was seperated at partition.And then- one doesn't need to see far to know what happens to minorities be they sikh or hindu or shia in pak.