Most Pakistanis do not have a proper understanding of how things are working in India. Their TV channels are very biased against Modi and hence, most of the Pakistanis feel that Modi is anti-Pakistan and that is how he won the election in India. They also feel that day to day work in India works around being anti-Pakistan, just as being anti-India is central to the identity of Pakistan.
Najam Sethi, one of the few sane individuals in Pakistan, discusses in this video about how Pakistanis have a wrong perception that PM Modi won on anti-Pakistan stance. Not everything in the video is right, but most of the things he talks about is right.
Here is the video: