Yeah, solid counterexample. Wikipedia and other Wikis have a clearly defined goal, i.e. collect factually correct information about a specific topic, which is also a goal shared by enough people to drive collaboration.
Another cool example is the Mutopia Project, which basically archives sheet music. Contributors can just pick a piece of music and transcribe that, and they kind of don’t even have to talk to anyone for the project as a whole to benefit.
But then there is lots of examples, like writing a new song, writing a new novel etc., where the goal is not clearly defined, where it’s difficult to collaborate, because what you contribute might not mesh well with what the others provide.
.desktop files are a Linux/Unix thing. Basically, it’s a fancy shortcut, usually to an application, which allows specifying additional infos, like e.g. translated names.
In particular, the contents of the application menu are defined by just a folder filled with .desktop files.
https://en.wikipedia.org/wiki/Shortcut_(computing)#Unix