It won't. Even Zidane, Pochettino or Jardim won't be able to get a tune out of Valencia or Young. Shaw is mediocre, goal and assist not withstanding. I have doubts as to whether he is suited for a Top 4 club. Lingard and Rashford are bang average and I don't think they will ever be anything more than squad players. Martial too is highly overrated.
However, we do have Sanchez, Lukaku, Fred, Pogba and Matic. That's a decent spine right there. Add Pereira who appears creative as well. If we hired a manager with a specific vision like Klopp's high intensity or Pep's possession based football, we can get a lot more out of these 4-6 players than what Jose is getting. While our FBs are still a problem and CBs are still inconsistent, an attacking manager would probably get us scoring more goals. Case in point -- against Brighton, if it had been an attacking manager and we were 2-0 down due to our poor defense, we could still hope to create a number of chances via Pogba, feed Lukaku and Martial, and score the 4 goals we needed to win the game. As it is, it ended 3-2 -- imagine if we created more chances?
Our problems run deeper than the manager, but the manager is a part of the problem and exacerbates it. We have no system or identity.