Yes but discoverability to what end? In one case the reader then thinks and says "I learned this on Stack Exchange" rather than a possibility of "I learned this

Yes but discoverability to what end? In one case the reader then thinks and says "I learned this on Stack Exchange" rather than a possibility of "I learned this from Mark". In one case an organization that is much complained about becomes even more of a necessity and so has less incentive to fix itself. In another the reverse happens. In hyperbole: in one case you may as well not post it, in the other case you may as well have not written it.