Look at Liverpool: Gakpo-Jota-Nunez-Diaz/-Salah (who may leave, but you get the point). Whether you rate them, or think they have reached anywhere near top form, at least you can see them making an impact, and trying to do something effective, every single game... the only issue is whether they are fit.
Now look at us: Rashford - Antony - Martial - Sancho-Wurghorst
We have one top player in Rashford, who has hit incredible form and consistency (but also needs to keep on his game...). The remaining four??? Well, I haven't a clue what we can realistically expect from the three who are actually United players, and then we have a limited player, with a great attitude, on loan.
This is a rebuilding process, for sure. The more I think about it, the more I think ETH is working miracles.