City have Fernandinho or Rodri deeper, with 2 of D.Silva, De Bruyne, Gundogan, Foden or B. Silva either side.
Liverpool have Fabinho or Henderson deeper, with 2 of Wijnaldum, Milner, Ox, Keita, or Henderson (if not playing deeper) either side.
Same theory, but they have better players.
You're spot on. What this highlights is that you don't have the quality of players.
Take away De Gea, Maguire, Pogba, Rashford and Martial and you have a mid-table squad at best.
First of all, i just saw that you're a Wolves fan so sorry if my mention of your team offended you in any way. It wasn't intentional, just the first club that sprung to my mind.
You're right about the quality of the players but it's not just that. There's this notion throughout this thread that the answers are pretty obvious and straightforward and that a two-time winner of the CL and his successor don't have a clue about how to build their first team. There's definitely logic behind Pogba's current role in the team and there's also a logic behind Ole's decision to create a transition-based side and not a possession-based one like City.
First things first. Guardiola sets his sides with the instruction to compress all spaces in the midfield and between the opposition's lines. He takes risks by positioning his defensive line extravagantly high on the pitch, by fielding as many creative/attacking players as his tactics can handle and by encouraging freedom off movement in the final third. The trick behind this is the certainty that his side is the one with the better players in these tight spaces: First touch, close control/ball protection, clever of the ball movement and high football IQ. If you put Mata, whose first touch is always sideways/backwards, and Pogba, who needs five touches and his positioning is questionable, in a three-man midfield and you ask of them to dominate the game in tight spaces, i'm sorry to say it, but you're asking for trouble. Ole can't play this type of football with this squad.
Then we have Klopp. I have no love for them scousers, obviously, but the underrating of their first team by many United fans on here has started to become very irritating. Fabinho is a modern defensive midfielder, quick to close down but also smart enough not to get bypassed easily. We don't have that type of player. The closer we came to "creating" one was when Herrera was utilized in this role. But even though Ander was good at collecting second balls and pressing, he got drawn to the ball very often and this made it easier for our opponents to get the ball behind him. We also have Matic who lately seems to turn around slower than an oil tank. Then you have Henderson. Nothing special indeed but his ability to find pockets of space deeper in the midfield and then play a through pass or pick the right time to switch play with his long diagonals is also something we lack. The third one, Wjinaldum, is a decent enough play-maker who can also make late runs in the box which is something that can not be said of Lingard, Pereira or even Mata. Furthermore, Liverpool possess wide attackers who are extremely good at using Firmino's movement in order to get behind defences.
I'm saying this because the problem is not the 4231. We've been there before, once the opposition adjusts we revert to our old poor form. It's about the roles of the players. And now we come to Pogba. We have a player whose passing skills are extraordinary but we also have a player whose positioning leaves a lot to be desired. I remember in Fergie's latter days at the club how Carrick and the back-four would pass the ball around (Zombie passing some called it without understanding its logic) and then Scholes/Giggs would suddenly pop up in a pocket of space and before you could count to... one, the long diagonal towards the winger or the through ball towards Rooney would be on its way. Pogba has the skills but he doesn't know how to pick his moments. Either because his bulk always helped him to keep the ball or because he lacks the intelligence, no one can tell but his coaches who see him every day in training. But he loses the ball often and he spends huge periods during games going AWOL and this is something that frustrates people.
So, play him in a more advanced role. But his bad positioning won't go away if he's being deployed further up the pitch. Going again back to Ferguson, one of his most inspirational managerial moves was to convince Rooney to play in the hole. Wayne in his prime did lots of things well but his supreme ability to find spaces in between the lines while facing the goal is an attribute of his that goes unnoticed by many. From that point onward, he could do at top-level what Lingard/Pereira can't do even at a decent one: Switch play, shoot from distance, play a killer pass, set a one-two... And Fergie's persistence on him playing that role despite Rooney's complaints demonstrates perfectly how a manager can pick the right fights if it's for the greater good and that a pat on the back is not the only way to keep your players content.
Pogba needs others to create space for him. Can we stretch the field horizontally with wingers able to go 1v1? Do we have attacking players who can hold the ball under pressure and function well in between the lines, thus allowing him to pick the killer pass? Can we get players on the end of crosses, so that the quick switch of play (from an advanced position) and a run in the box will become a viable option? Look at France, it's Griezmann's continuous movement, M'bappe's threat of pace and skills on the ball and Giroud's strength and ability to harass defenders and finish in the box that unbalances defences. Pogba provides the finishing touch, the good passing skill & vision that will make the most of all the others' abilities.
What do we have? Rashford can only run in straight lines. Martial's best movement off the ball is (still after all these years) the early run between CBs when we regain possession. Our #10s need space to do their thing, whatever little that is. And here we are discussing why both Mourinho and Ole decided to go into a season with Pogba playing deeper and aiming to set up on the counter our attacking players who, wait for it..., rely heavily on pace and little less to score goals.
There are problems with Pogba in both roles but the logic behind Ole's initial plan isn't at fault. The biggest issue is that we have allowed ourselves to be fully dependent on Pogba having a good game in order to win football matches. Play him in a three-man midfield? Yeah, but only if you have a solid DM/HM (McT can be that player) AND someone like Kroos, a player who can create triangles even in a phonebooth. Otherwise, we'll be looking at the same problems again.
This is a more general post and my thoughts about the OP's question. I wish to make clear again that i wasn't trying to be cheeky.