Simple question. Is the word "Entschleunigung" in the genitive case? So the genitive case does not require -s or -es when not accompanied by a definite or indefinite article?
That's a good question. First of all, we should note that the genitive doesn't always require an
-es, just for the masculine and neuter genders. The feminine gender (to which Entschleunigung belongs) does not.
Secondly, this is a construction called the partitive. It shows up in other common situations, like the following:
Ein Glas Wein Eine Tasse Kaffee Eine Art Entschuldigung
As you'll note from the link, the actual case of the second noun in a partitive pair is actually not set in stone, although without any adjective it's essentially just nominative. It can also match the case of the first noun, or appear in genitive.
Here's another question with more details for you.