Ok, let's play along.
"Much better" as in conceding fewer goals or "much better" as in scoring more goals...or both?
For a quick refresher, this is how we stacked up against City in terms of goals conceded and goals scored:
Goals Conceded
City 33, United 43
Goals Scored
City 94, United 58
A goalkeeper's primary but by no means exclusive responsibility is to prevent goals from being conceded, to keep "clean sheets". Our record of 43 goals is 10 goals worse than City's record and Dave has to take his share of the blame for some of those goals, such as the goal Benrahma scored when West Ham kept a clean sheet against us. But 43 goals conceded is the same number of goals conceded when we last lifted the PL trophy in 2013 and is only marginally worse than the 37 goals we scored in the PL title season of 10-11. For further context, Arsenal this last season, with the presumably modern keeper Ramsdale in goal, also conceded 43.
For a club to become a PL title winner, goals conceded needs to be closer to 30. But of course it's a team the defends well and I trust you will acknowledge that City have a vastly better side at every position than United.
Which leads to the next point -- goals scored. There is no fukking way that even if we had Ederson, let alone Onana, in goal this last season that our goal production would have increased by even 10 goals, let alone 36 goals. Apart from Rashford, who would likely not make the City starting XI, our front line was shambolic this season and as much as we might be tempted to explain it away on injuries, mental health issues, the difficulty of adjusting to the PL the sum of truth is that our front line was shocking and shambolic for most of the season. Even if we had Ederson or Onana spraying the ball smartly to our fullbacks if our front line can't do their job we're not scoring goals. Maybe we inch up a few goals on the back of a few inch perfect Route One balls to Antony or Rashford, but such a ball to Antony gets wasted as his movement was perfectly predictable and easy to defend. Maybe Rashford would have scored 2 or 3 more goals on top of his 17 PL goals but surely no one will argue here that Martial would have scored 10 more goals, Weghorst would have scored 5 or 6 goals or Elanga 3 or 4 goals. Whether it was lack of interest (Martial), lack of ability (Weghorst) or lack of whatever (Elanga), our goal scorers were vastly short of what was required and none of their deficiencies can be blamed on De Gea or even on our midfielders. Bruno is a bit inconsistent for my liking but is a fantastic attacking midfielder, Casemiro was a revelation after initial doubts seemed reasonable, and until Andy Carroll cut him down Eriksen was fantastic.
For a club to become a PL title winner, goals scored needs to be at least in the 80s and no keeper on the planet, or who has ever lived, would have turned Martial, Weghorst or Elanga into goal scoring machines. When you have a deficiency at CF you know what you need to do? Pick up a proper CF.
Bring in Obana and we will see smarter passes to our fullbacks, but if our RBs performed at the level they did most of this season opposing teams will invite the ball to our RBs, press the crap out of them and regain possession from them. But if we bring in Onana at the expense of bringing in a proven CF the 23/24 season will be another top four season, no PL title challenge anywhere to be found.
