Don't forget this is all make believe. You won't need to re-live the lives of everyone there ever was, as implied in this creative writing.
"Once you’ve lived every human life throughout all time, you will have grown enough to be born".
There's no magic number of humans that represents "all of them". It's odd to suggest that people (even aborted foetuses?) are only part of a giant equation, that permits one into heaven, or whatever is suggested here.
Please, this is not a lot different than believing that the large round boulders on the hill were laid by crocodile spirits a long time ago. Lovely story and belief of a particular native people. But those boulders have quite a different origin - nothing to do with crocodiles, and their fate has nothing to do with crocodiles either.
A conversation isn't waiting on the other side. Death is the end of conversation, not the beginning. We only hope it will mean beginnings and re-incarnations, but the chances are that when you die, you're done being human and you'll be onto something else.
LOL, progressing up through the ranks of humanity to reach God-status. That is some messed up mass-ego injection.
Edit: I suppose it's just as horrible regardless of whether or not you experience them...