I see that Arsenal dominated literally everything and I'm not surprised that this was reflected in the score. As for other opponents, there will be a different situation, and so far no one knows who will be stronger. If I were the manager of United, I would at least take care to confidently beat outsiders and average teams, this team is hardly capable of more.
Arsenal dominated the first half, while Manchester United struggled to perform well initially and if we think it for a moment that the controversial offside call by VAR that disallowed a potential 2-2 equalizer for Manchester United was not made, I do not think that Arsenal would have still been able to win the match. And one thing is sure the result proves how competitive the Premier League is but there is still a noticeable gap between Manchester City and other teams in the league.
Manchester United actually already has a good squad. It's just like last season this squad has not shown their maximum strength. But in the match against Arsenal, several players like Rashford have started to show their sharpness again. My estimate is that next week Manchester United will return to their maximum strength again. Because a coach like Erik Ten Heg should be smarter than this. He must quickly provide motivation and make the players' confidence return to what it was at the end of last season. Don't let the Manchester United squad repeat the mistakes like at the start of last season.
But for Arsenal I am starting to see this squad really getting stronger every season. Arteta is indeed a talented young coach. I always expect a lot from this coach.