Most barriers to learning are political

 Most barriers to learning are political. 

Broadly, barriers to well-known knowledge are often mere [ absences of algorithmic documentation ], a.k.a. [ incomplete documentation ].

Often, incomplete documentation is tolerated as a class-filter to moat out new members of the organisation, or community, who are class-aspirants seeking upward mobility.

The completion of documentation, depends on economic incentives ... sometimes a shortage of learned people, raises the bidding price, making documentation worth paying for; sometimes an abundance of charity, creates  documentation philanthropically, lowering the asking price.