I think you're getting at the idea that instead of having objects differ in their behavior by overriding methods, you have them differ by having fields bound to objects that implement different behavior.

Assuming I understand you right, that's an excellent insight, but it's just the classic principle:

Favor object composition over class inheritance.

There's nothing new in that idea or anything special to ECS. Do you know how I know? Because that sentence here is directly quoted from page 20 of "Design Patterns", which ECS and DoD are often claimed to be in direct opposition to. :)