Sadly, in an aircraft fire where the cabin is fairly involved, survival rates are very low for those who cannot self extricate down a slide or aren't near an exit. Cabin is a Class A fire environment in and of itself, even without Class B accelerants, and once even a small fire starts, the heat build is so rapid that items begin burning and self-igniting quick. Interior temps rapidly go from 1500+ degrees near the ceiling, to about 130+ at the floor, and the toxic gases build and descend to the floor so rapidly, that survival time just due to these gases is very short. Granted, a fire of this intensity, it will crown very quickly, around 90 seconds, through the roof of the aircraft and self ventilate, but that doesn't help those onboard, especially if it flashes over first.
Rescue of persons trapped in this environment is very tough, if not nearly impossible. During my last ARFF recurrent, we were running 4 person interior teams, 2 on 1.5 inch handline followed by 2 for rescue. Inside the aircraft, after making entry through the left overwing exit in dusk conditions, visibility was about 6 inches, even with the beam of the flashlight, until reaching the fire area. Still, we were only able to make rescue of 4 persons on the exit row and a few more about one or two rows each way from there, before being about 40% air remaining and bushed from the effort of laddering the wing, hauling the hose line up there, all in full proximity gear, etc. The hose team had more air and could continue further inside, but they are fighting fire and attempting to suppress, not rescuing necessarily. This doesn't take into account the real-world of aisles blocked with persons and bodies, jam-ups near exits, maneuvering of hoselines in the confined interior area, etc. So realistically, in a cabin fire scenario with a fire starting and not controlled, unless you get out yourself; chances of being rescued from anywhere other than about a few rows from an exit are slim. And remember, with the majority of ARFF departments, manning is fairly low with some trucks only having 1 crewmember onboard, depending on the airport. For interior fires, often one or the other of rescue or interior firefighting have to be performed, unless multiple exits can be opened.
Pax have to conted with the toxic gases far before the thermal nature of the fire ever gets to them. So you'll choke to death long before you ever burn to death. It's just not an environment conducive to survival. With water use in the cabin only (no foam is used if possible), there's always the steam component which we try to avoid, but can't always be avoided.