Yes, I would not dispute your statement, but that does not contradict the fact that airframe weight is minimized to increase efficiency. I did notice the seats

Yes, I would not dispute your statement, but that does not contradict the fact that airframe weight is minimized to increase efficiency. I did notice the seats were mostly metal, but I also noticed their (essentially) honeycombed design: they are mostly the rigid frame, rather than solid metal. I'm sure if they could reasonably remove the ram air turbine, they absolutely would (both for cost and efficiency).