Wikidata needs sources: "without sources we are just not credible".
A fine argument, it rings familiar. However take this item as an example, it is bulked up with sources. It has five sources and the second statement that is informative, the "date of death" is added to the fact that this is actually a "human".
The two statements that are informative do not have a "source", they are however useful. This human is from Sierra Leone, he used to be called "prof" and, he is a writer. Possibly you find it in the five sources. When you don't, there is always the Wikipedia article to read.