One weird thing with rents Germany is that old contracts have very low rents that barely increase over the years. So, you get this weird dynamic of very old shops and restaurants that have been there for decades paying almost nothing right next to very hip/trendy places that have to pay through their nose for the privilege of being there. Some of the older restaurants get away with this by simply charging less for their food and drinks. Newer places can literally not afford to do so.

Especially West Berlin still has quite a few places that pre-date the fall of the wall 30 years ago. Lately, Charlottenburg (a big neighborhood in the West) has been gentrifying rapidly. So, you get this weird contrast between these old places and very new & trendy things opening right next to them.

You see the same dynamic in East Berlin though large parts of that have been gentrified by now. I live close to the wall memorial on the East side and most of the old shops and restaurants in my area have disappeared over the last 12 years. Mostly the reason is that the business owners hit retirement age and scale down or sell their business. In some cases, a relative takes over but more often than not the place closes and some other business moves in.