I don't want to make this sound like I'm disagreeing with you for the purpose of doing so because I do somewhat know what you mean, but from the bold bit, it sounds as if you're saying he was in second gear because of the fact he hasn't ventured forward much, and this is what I'm trying to point out.
With Bruno, and the attacking prowess of Martial, Rashford, and Greenwood, all Pogba has to do is to provide the ball to them. Previously, we didn't have that, so it felt as if he had to do everything, and when he didn't, it was all his fault.
If there's games we're losing or feel we can get a few more goals to kill the game, we'll no doubt see Pogba attacking more like the Spurs game you mentioned.