Shimano has a lot of non series parts specifically for the OEM market, so do many other companies, FSA just being one, nothing wrong with any of their products, either retail or OEM.

If Shimano is the 'genuine article' what were the long since gone companies who made parts before them?

For the late great Sheldon Brown, the ISIS bottom bracket failure you are referencing isn't really relevant in 2013, that article is getting on for 8 years old, about a component which is no longer made, and for a BB type which is all but obsolete.