There’s a difference between being a captain and a leader.
You’re given the title of captain when there’s no superior option to you, and you’re performing well enough and ideally have the personality traits to lead.
You’re not given the title of a leader. You earn that title.
Imran played the role of selector, father figure, fitness coach, and took full control and responsibility of Pakistan firing as one cohesive unit despite all the typical big personalities clashing in an already dysfunctional cricket system. Under him, Pak finally played as one team.
If you are looking for a statsguru answer, maybe you will conclude that someone else as captain led their team to a better w/l record and so you think that person is a better captain. So be it. If anything, with context Imran has a fantastic record in that regard too.
But for me, Imran was the first and possibly only captain we had that instilled the discipline in team Pakistan to consistently compete with the world’s best and actually behave as a professional sports team which rises to the occasion rather being an “unpredictable”, volatile and self destructive force of nature. Task he had on his hands was far greater than what Kohli had to do who was served a ready made talented team and possibly the best cricket structure support in which billions of dollars have gone in.
Just look at what happened after Imran left. Post 92’-2010, Scandal galore in match fixing, always falling short of what could have been memorable victories, 2009 t20 WC excluded.
If Kohli leaves captaincy, India would not fall flat on its face as a team.