My knowledge is very limited to media reports of what happened at the Grenfell Tower, but what happened, and why we're referencing it, is that it's an example of a building that was built to code many years ago but then it got renovated. They put on an exterior cladding that was a combustible material, not a non-combustible exterior cladding. This allowed that building to become overwhelmingly engulfed very quickly, to the point where the firefighters had difficulty. When you get in there and you start looking at high-rise buildings that have multiple occupants, it becomes a matter of evacuation and let the fire grow or can you suppress the fire and concentrate strictly on evacuation in a safe manner.
What happened there, in my opinion, was that fire grew so fast they didn't have the opportunity to even offer a safe egress for many of the occupants. Did they suffocate? Most likely. I think you're correct in your statement that most people who die in a fire die from suffocation versus from the heat and the flame. Most people don't even see the flame, they just die of smoke inhalation.
The reference is because of the combustible cladding and what that did in letting that fire grow to such a degree.