> I yet have to see someone actually argue that you don’t need to understand SQL and ORM will suffice

Well that's because decades of bitter experience has told us all that object graphs rarely map cleanly to sets of relationships.

However, I do think that must have been the original idea as tools such as Hibernate tried so hard to obscure the underlying SQL and database. As a result all Hibernate objects have their own particular identity requirements which only made sense to a developer that knows what's going on under the hood.