I had blogged briefly about pyDAL here:
pyDAL, a pure Python Database Abstraction Layer:
I'd worked as the team leader on one such database middleware product, written in C for Windows, some years ago. It was successful, and somewhat widely used in projects for clients at the company where we built it.
Such products can enable you to write less boilerplate SQL code, and also to work at a somewhat higher level of abstraction, thereby providing some productivity.
I agree with some of the other comments here, that 1) such abstractions can sometimes be leaky, and 2) SQL is not hard to learn (for the basics and a bit more - hell, it used to be considered bread-and-butter tech), but for some reason there seems to be an impression that it is tough, from the last few years - sometime after Web 2.0, maybe.