It does not replace OOP because there are no answers to other questions like: does it support polymorphism? Or data encapsulation? Etc. It's a data access design principle, and that's about it.
To the same degree that SQL does. The answer is, "yes, no, does it matter? is that even interesting?"
It is - it's just called SQL and is considered the opposite of cool.
It's kinda shame that people try to cram it into rigid object model instead embracing flexibility on the code side too.
That's just structured procedural programming - subroutines mutating separately-defined data. This used to be all the rage before OOP took over!
I would have agreed with this whole-heartedly when I first started using ECS. It has its own difficulties though.
Like what?
Explain "entity" to someone that is just starting their software development career ;)