I tend to blame the impedance mismatch more on the popularity of "entities" as a way of doing domain modeling in object-oriented programming. It's far from the

I tend to blame the impedance mismatch more on the popularity of "entities" as a way of doing domain modeling in object-oriented programming. It's far from the only way to do domain modeling in an object-oriented language. It's not necessarily even a particularly good way, and it creates problems even if your app comes nowhere near a database.