score:10
Some things do have a kind of break during the summer (one that comes to mind are the opera houses but isn't it true of opera houses everywhere?) but shops will have normal opening hours. Cafe are definitely open, I don't think libraries have limited hours, don't know about co-working spaces.
Some offices might be a little less busy but it's a large city with many tourists so it's not like it's closing down in the summer like a ski resort. The crowd might be a bit different but the streets certainly aren't empty.
On the other hand, there are a number of summer-only things to enjoy in Berlin: beer gardens, outdoor cinemas, beach bars on the Spree, floating swimming pool, al fresco dining, biking and other activities in the lakes and parks around the city, etc. so it's definitely worth experiencing in this season as well.