It's both. But he's a different type of attacking midfielder. He doesn't need to be a big goalscorer in some teams. Stylistically, the system that would get the best out of him is one similar that Zidane would succeed in, who also was never much of a scorer. Same with Iniesta. He's not a pure number 10, doesn't work in any sort of team that United has ever really had, but also not a controlling midfielder in a Pep type team. He could be the most advanced/free midfielder in a possession team, but generally he's always needed to play as the most advanced player.
There's 0 doubt in my mind that we've completely wasted how best to use him, through a mixture of how we generally have always played but also awful coaching appointments in his time. I'm not absolving him of criticism... but I do think had he chosen to go elsewhere that summer instead of United, Pogba would have been seen in a completely different light. But he joined an ever failing team who played him outside of his best position every time, just to shoe horn as many other star attackers in as possible as he can "kind of play deeper".