familiarization is the basic of the basic requirement for doing anything anywhere.
Compare:
https://duckduckgo.com/?q=contributing+to+stack+overflow
https://duckduckgo.com/?q=contributing+to+the+linux+kernel
https://duckduckgo.com/?q=contributing+to+audacity
https://duckduckgo.com/?q=contributing+to+gnu
The closest I found to an answer on SO was marked as a duplicate by several people with no link to the previous answer.
Maybe a bit circular, but maybe someone should post on SO meta to improve the documentation?
The comparison with open-source isn't apt; inclusion in the mainline of an open-source project affects every user of that project. Keeping code that does not fit with the goals of the project negatively impacts existing users of that project.
Not so for SO questions, or for Wikipedia pages; a page or question you never see, but contains useful information you don't personally think is notable (or "constructive"), costs you nothing to keep.
This is just the Wikipedia editorial/deletionist problem. Some people are more interested in enacting and enforcing process and community "norms".