Yes, they're in two comparably large and affluent German cities (although each of these cities has numerous clubs), but when it comes to sport club success I think city details is just one factor. Ownership wealth and dedication, current management issues, and recent luck are important factors.

For example, Boston has way more championships in US "big four" sports than every US city except NYC, but there are 24 larger cities in the country. There are just a ton of factors at play (pun intended).

https://en.wikipedia.org/wiki/List_of_U.S._cities_by_number_...