Actually, many such leaders have come in Ummah after Khulafa e Rashideen, he is not the only one. Not necessarily, all of them were rulers.
But majority of them were either killed by fellow Muslims, or Muslim rulers of their times.
Finishing his popularity is not possible without bringing him back.. that is the only way possible because current economic downfall requires divine intervention, which I am not hopeful will come for Pakistan.
Remember one thing, the one who raises the name of ALLAH SWT's beloved prophet (PBUH), He SWT raises his name to the heights unimaginable. We don't realize this but success does not depend on winning a battle here in this world, success is what Imran Khan is going through, he is living every single moment of his last days as a successful man and once he is killed (which I am sure will will be), he will be remembered as a hero of Muslims for many decades.. we may witness books on him and PhDs offered on his ideology just like Allama Iqbal. It is expected because he raised the prophet's (PBUH) name among those powerful leaders who hate to hear that name in their dreams even.
He never lost a battle in his life, and this last battle will be won, though we may not realize it. He has successfully defeated an ideology that kept us captured for decades.. the same ideology termed anyone against that a traitor... now that ideology is synonymous to betrayal for the majority of this country. If this is not a war lost by the powerful, then what is?