It's too early to say. Manchester United played well in the first week against Arsenal, although they did lose, but their performance deserves praise.
Because of this, many believe Manchester United can do more in the upcoming matches against Fulham and Burnley. I agree with that. In fact, this is the right time for Amorim to improve the team's mentality and confidence, especially since it's still early in the season. So before it's too late, like last season, when they were already so far behind, it would be difficult to recover. So I think Amorim knows what they have to do now.
Arsenal are second favourites for the title after Liverpool in the bookies' eyes, so a poor first round result really doesn't matter that much. Most teams will drop points against Arsenal so the situation will be evened out for United. But now they need to take 100% of the points against Fulham and Burnley as they play City in the 4th round. If they lose at least 2 points in the next 2 games, then United will have 4 points after 3 rounds before playing City in the 4th. Yes, they might win against City, but still the risk of being left with 4 points after the 4th round will be very high.