There is a difference in quality between these two teams and the victory achieved by Bayern was quite convincing, the final score was 4-3 but that was because the Manchester United team were able to reduce the deficit at the end of the match, but if you look at it overall they deserved to lose because of their performance they're pretty bad.
It seems like there is no difference in quality between the two teams, but what there is is a difference in circumstances where Manchester United this season is still looking for the best strategy to be able to win every match while Bayern Munich has found it when last season faced quite a lot of obstacles and made several changes to their squad and so far this went well so that not only in the Bundesliga but in the Champions League they managed to win.
7 goals were scored by both teams and this match was quite interesting because I thought Munich would win with a large goal margin because seeing how Manchester United lost in a local competition in front of their own public would affect their mentality but apparently not even though Casemiro scored two goals in the final minutes of the match but at least showed that United was not below the quality of Munich.