I have cedar chips in my chip mix (it would be literally impossible to get wood chips around here without cedar mixed in, as it's simply part of the environment) and I use aged chips in both coop and run. Little to no cedar aroma at all. I feel very comfortable about using it in my set up. We have Western cedar which is lower aroma than Eastern red cedar (which is more aromatic and the type of cedar associated with hope chests and insect repellents).
I would probably avoid using cedar shavings (the increased surface area allows for more offgassing), or fresh cedar (well, fresh anything really... pine sap is awful!), or cedar in closed-in environments (i.e. indoor brooder, coop lacking in ventilation), especially if it's an aromatic variety of cedar. My coop is well over recommended ventilation plus has a high ceiling for added air volume.
Many coop builds have cedar and I don't think people ever consider that. My current coop has cedar trim, my old one (which is now a chick brooder) is 100% cedar.
Obviously if you're not comfortable with it, don't use it, but I've been mixing in cedar for the last several years and there's been no sign of respiratory issues in my flock.