Reasons why there was no voice-acting is completely different from "lack of resources". Swen mentioned it was dictated by the way their dialogue system designed. That's why there is keyword system in 90% of the game dialogues and only personal ones have real replies and writing.
You can't voice a reply because it may be spoken by completely different characters and of different gender (many of the share the same pool). Voicing all of these with every actor? Are you serious? Such thing wouldn't be able to pull out even Bioware with their publishers.
