I suspect it's mostly marketing. People think "I don't want code so I won't use Codex" so they get the same thing but labeled Work.

+1 I’ve had this conversation with so many non-techies. They assume Codex can only do coding.

which is again where Anthropic has outplayed them. Because Claude is being happily applied everywhere as a universal term, with "Code" or "Cowork" only appended as necessary.