This is a football and things will not happen as we said it all the time. I would say Manchester City are going to win the title this season again even if Arsenal are going to be unbeaten with their remaining matches because the same thing will also happen to Manchester City. I believe Manchester City will not get defeated by any team at the moment because they have already topped the league and have a few games to be the champions, so did you expect they would also want to lose? No, they won't; they will focus, and the fact that they don’t have any other competition is a distraction. They are going to come with their full squad in all their matches.
Mancity's goal now is too clear and it is difficult to stop them from successfully defending the Premier League championship. Everything is on their side as the remaining matches are quite easy for them to overcome. But it's a different story for Arsenal when they have to face Man Utd away from home.
Although Man Utd has played poorly this season, when playing against great rivals like Arsenal, they can completely make Arsenal's championship dream disappear. Man Utd is currently out of chances to reach the top 4 but is still fighting to win a place in next season's European Cup. They still have the goal to fight hard against Arsenal.
For Mancity, the most difficult match remaining for them is probably the match against Tottenham. They are also racing for a spot in the top 4, however if Aston Villa officially wins 4th place before Mancity's match against Tottenham, Mancity will only have to face a demoralized Tottenham. And then, winning all 3 points is a fairly easy task for them.