As the entry level for self-publishing is now very low, there is a whole swamp of the low quality content. Once you join this swamp, it is very difficult to raise above it, as nobody can find you. A good quality content initially belonging to this swamp takes long time to be noticed, if ever.

It is critical to have the public reviewing system not for picking best of the best but first for discarding the really low quality junk. Automated search tools, even Google technologies, cannot do this properly, as the junkwriters are often much more experts in "search engine optimization". Hence they trash with lots of revenue generating ads around somehow always takes if not the first then at least a second place in the search results. 

The only way known for me to mitigate this is to link (or publish in) the official website of the notable university. Web search will take this into consideration, but the option is not easily available for all potentially good publishers.

It is the lack of the serious public reviewing system that hinders publishing of the free content.