Board Thread:Questions and Answers Forum/@comment-205.222.248.88-20161114165016/@comment-26355186-20161114183016

That's likely because of the fact that there was a total of six different voice actors for the Guardian. Bungie possibly felt like it would've been profitable to rehire them all. It's also possible that not all of them were available at of the development of The Taken King, and so Bungie chose not to do any voice lines whatsoever. Considering the way the internet is, I don't find it unlikely that there'd been outcries if, say, the Awoken and Humans got lines, but not the Exos, or perhaps worse, only one gender of each race were voiced.