Bayern Munich and Leverkusen are both very strong and well performing teams. Due to which the match between them was difficult. If you have seen their match, Leverkusen also managed to score only 1 goal, although they are also a strong team. The reason for this is that Bayern Munich's record is very good and strong, if you look at their close matches, they have only lost 2 times, so I don't think there will be a better record than this because they have a stronger team in their record. Even a match must have passed with defeat. We should also see that Leverkusen is better than Bayern Munich which is why they won this match but it would not have mattered to Bayern Munich but they will definitely want to win this match because they are a strong team.
Leverkusen were the winners anyway. They benefited from the red card that Munich got. However, they didn't really play with an advantage over Munich who in fact were also able to create quite a lot of chances.
The result might have been different if there was no red card at the beginning of the first half. But this is football with all its surprises, Munich must accept this result and can focus more on the Champions League and Bundesliga.
Perhaps it was better for Bayern Munich that they were eliminated from the German Cup. It is now time for Bayern Munich to focus more on the Champions League. They will probably have no problems in the league and will be Bundesliga champions at the end of the year. However, they need to be very careful and prepare well for the Champions League. The results they have achieved so far are not very successful. What was expected from them was to advance in the Champions League in the first eight. I think it was better for them to be eliminated from the German Cup in order to advance by winning their remaining matches.