I am not for Pogba being made captain, but I understand the debate around the topic, seems fair to me. The reason I'm not for him being captain is because I want the captain to be someone who of course has the talent to be a regular in the first team but also sees himself as happily staying at the club assuming we are competitive. So far I believe Pogba will want to move the Barca or Real at some point plus he has Raiola as an agent who will go around every summer putting his player in the shop window to at worst increase his contract, that makes Pogba ineligible for the role in my eyes.
If handing him the captaincy changes all that, then I can get down with the idea. Barring Juve or PSG, I don't see him ever being given the captaincy at Real, Barca or Bayern.
I disagree with your assessment of his world cup performances, as in you are a bit too harsh. Coming up spades versus a rather good and combative Croatian side comprising Modric and Rakitic in a world cup final is not a feat to be scoffed at.
As someone mentioned ahead, there is no one in his age bracket and in his position that brings the variety of qualities he possesses on the ball to the table. His issues are linked to a lack of maturity, but he has made quite a few big finals now, there is no reason not to believe that those experiences won't help him figure himself-out and become the consistent midfield general he has the potential to.