They’re different fields for different intentions really. I guess depending on what you mean when you say “replace,” but to me, I wouldn’t say one replaces the other. It’s really apples and oranges to me.
ETA: And, yes, I understand that this version incorporates ideas from BoL into it. Keep in mind when fields are integrated together, it’s not the whole fields coming together. There’s always some tailoring that goes on. And then there’s the changes that occur in the creation of the new, integrated field. It’s like when you add sliced onions (BoL) to a stew base (Eternity), when you cook it, sure, the onions are there, but they’re going to look and be different from the chopped onions you started with.