What difference is that?

There's a causal connection in one case that is absent in the other, and a correspondingly higher distribution in the pasts of similar worlds.

I don't understand what you mean by "only a duplication".

Duplication of effort as well as effect with respect to other parts of the universe. Meaning you are increasing the numbers of immortals and not granting continued life to those who would otherwise be deprived of it.

Suppose that you were to have a biological child in the traditional way, but could select whether to give them genes predisposing them to extreme depression, hyperthymia, or anything in between. Would you say that you should make your choice based on how common each temperament was in the universe, and not based on the impact to the child's well-being?

We aren't talking about the creation of random new lives as a matter of reproduction, we're talking about the resurrection of people who have lived substantial lives already as part of the universe's natural existence. If you want to resurrect the most people (out of those who have actually existed and died) in order to grant them some redress against death, you are going to have to recreate people who, for physically plausible reasons, would have actually died.