They could have certainly won the game even without Ronaldo and Pogba on the pitch, but you have those days where you can't turn your dominance into success.
I think one interesting moment in this season will be the half time around December where we can see whether Manchester is still close to the top teams or even themselves the team at the top. They do have the players for it.
Manchester United have had a lot of these days recently they have drew or narrowly beat opponents in the dying seconds of the game. I am not impressed by Manchester United Ronaldo is impressive of course but as a team they are lacking that creativity and I think the midfield is to blame. Ronaldo might have scored most games that he has played in but he needs more service and I would expect him to score 20+ goals this season in the league.