I think there are key differences. Halsey seems to be motivated by what she can do, ignoring questions of right or wrong, even recklessly. Librarian seems to be motivated by what she must do, because of her sense of right and wrong, with great care. I suppose they're both pretty detached for either of those to be possible (both assume they must be the ones to act, which eventually is a product of pride). But Halsey's work was self-preserving, whereas the Librarian's was self-sacrificing. Did they both go too far? Probably.