The issue is not with the writers, but with music composers. In a music band, this job is the most important as a great band is known due to its great compositions. Most of our singers in the past made their own compositions and melodies and became overnight sensations. The list is quite huge - especially in 90s when almost every week there used to be a new singer or band popping up: Nusrat Fateh Ali Khan, Abida Perveen, Alamgir, Shehki, Hassan Jehangir, Ali Haider, Shehzad Roy, Ali Zafar, Abrarul Haq etc. That they had a good voice was a plus, but that was not the only skill they possessed. The ability to churn out great compositions was one of the main reason their songs became timeless.
On the bands side, Junoon created great songs mainly due to genius compositions by Salman Ahmad. Later, Ali Azmat produced some good solo songs, but wasn't that successful as he was in Junoon days. Same goes for Vital signs or Awaaz as the collective efforts were better than the solo ones.
But now music industry in Pakistan is dead. What we have now is singers with good/great voice. But almost all of them serious lack the ability to produce great original compositions. That's why they are just reduced to making remixes, fusions, and other junk that is sold in a fashionable way in Coke Studio. I can't even think of any great original song in the last 10 years produced by the local industry.