I suspect they knew what had to be sacrificed in order to save the structure. A lot of Monday-Morning Quarterbacks criticizing the Fire Fighting effort.
From what I’ve been reading in the foreign language press, there is plenty to criticize at the decision-making level.
IOW, the firefighters are not the problem. The people hamstringing them are.
The exterior stone walls may have been preserved but I also imagine some heat damage to the massive stone. Clinkered faces, mortar cracked by heat, etc. etc..
From work in all sorts of new construction and old structure renovation, I want to advise people that old structure with what is called Heavy Timber construction does normally have a certain resistance to going up suddenly like this one did.
I was thinking that the roofing was turne metal construction or similar non-flammable exterior on top of wooden deck joist on heavy timber arches.