My two cents......
If Pogba leaves for UTD under the conditions that we keep reading, for 120 mil and a salary 3 times bigger than what he earns at Juventus right now, i wouldnt hold any grudge against him. I would be 100% cool with it, and will only wish Pogba good luck. Why? Because its 3 times bigger salary than what he earns now and that is A LOT. Secondly, there are people saying that if he moves, it would be a step down in his career which i strongly, 100% disagree with because imo he would excell in Man UTD because they dont play CL this year and the pressure is far lesser and will be lesser on the players and management there. Football fans, other than the Juve fans, were saying that Vidal was also making a step back in his career when he decided to join Juventus, a club that has finished 7th place the season before, no CL ect, but look how that turned out, he became one of the best midfielders in the world.
It shouldnt be strange at all if Pogba does leave for UTD because, objectively, there is not a single diference between Juventus and Man UTD only that Juve plays CL this season and UTD doesnt, and that is not even so important because it is only one season.
Bottom line, Pogba can do whatever he wants, and whatever he decides, i would be completely ok with it.
From Juve's point of view however, selling Pogba would be taking two steps backs after making a step forward with the signing of Pjanic. No player is irreplaceable, but at the moment, Pogba is a vital part of Juve's European future.