There might be more agreement here than meets the eye. Drexler often posts informatively and approvingly about progress in DNA nanotechnology and other bio-related tech at http://metamodern.com ; this is the less surprising when you remember his very first nanotech paper outlined protein engineering as the development path. Nanosystems is mainly about establishing the feasibility of a range of advanced capabilities which happen to not already be done by biology, and for which it's not obvious how it could. Biology and its environment being complicated and all, as Jones says.

Freitas in Nanomedicine addresses applying a Nanosystems technology base to our bio problems, or at least purports to -- I haven't been able to get into it because it's really long-winded and set in tiny type. Nanosystems was more inviting.