I don't think Latour's criticism of social theory applies to the causal closure of physics, or science's claimed exclusivity to describe fundamental ontologies; it criticizes the approaches of 20th century post-modernist critique.

Are you familiar with his follow-up, 'Reassembling the Social'? I'm not, but in reading a summary it seems to propose better methods for comparing ontologies and systems.

It's been a long time since I read that. After posting the link, I reread it, and it seems I misinterpreted it somewhere along the way. I thought that it develops an opposition between "matters of fact" and "matters of concern", and that it breaks along the same lines of the discussion here, but it doesn't.