Pogba will probably leave in the summer and we won't need to be devastated about it because he's never maintained his best standard for us. But he's a quality player and if he can keep playing as he has done for the past month then that's great.
He's scored a goal in the World Cup final. He could have spent the past four years winning league titles and Champions Leagues elsewhere. He's largely spent his time at United playing with people nowhere near his level and I imagine that's frustrating.
Think on a human level, and yourself in a work place when those around you are largely incompetent (which has been the case for Pogba for the majority of his time at United), it's unlikely you work to your peak level. It's not ok, when you're getting paid, but understandable.