What did is Furnace and heavy smoke. People in the back had no chances unless they bolted from their seat going forward, before even the aircraft came to rest.
So can we give a rest with this luggage issue in this topic!? Or just start another one specific to it.
What did for those in the back (as others have noted above) was the G-force effect of the first and second bounce. I suspect most of the pax behind the CoG were incapacitated by severe fracture/ head and spinal injuries / loss of consciousness, or blocked in by other pax suffering those injuries. I've seen what a 50-seat bus looks like when it's rolled, and I doubt it was much different inside SU1492, even before the fire broke out. A handful of trolley bags on the escape slide was the least of their worries.