I think it depends of the kind of support he would get. I think he's shown he's not afraid of spending big and stick to his guns even if it doesn't start well, like Paulinho, but also he's willing to drop fan favorites if they don't fit in his ideas, like Slimani or sell hyped youngsters that don't exactly fit in his system, like Chermiti. But Sporting's board has had his back, they have trusted him all the way and they have given him time and resources after a bad season last year.Would it work out at United for him or is it too big of a step?
I don't know how toxic things are at united at the moment, but with the right backing and some patience from the fans I really think he would build a great team.