The demise of Pak fast bowling started with decline of Reverse swing, the earlier greats of 80's and 90's thrived on it. They would MAKE the ball, with Pepsi bootlecaps as there were no cameras to monitor, then all they had to do was wait for ball to get old. And once it did, just bowl as fast as possible and deceive batsman with guile and speed.
Just see the record of Wasim / Waqar / Akhtar / Umar Guls with new ball vs old ball, it's chalk and cheese. The teams would regularly crumble from 115/2 to 160 all out.
Things have changed now, so many cameras, far higher and career threatening punishments if caught, have essentially seen the decline of reverse swing.
And that's where the problem lies with Pakistan, the current crop is compared to earlier ones but these poor chaps are handicapped as they can't swing the old cherry. Imagine Shaheen Shah Afridi bowling in 80's under Imran Khan with a made up ball, this guy would run through sides every day.
So on topic this jazba and Junoon may not revive pak fast bowling, having Waqar as bowling coach is also pretty dumb, that guy took years in international cricket to learn how to bowl with a new ball.