Probably not clearly recognisable to a British reporter regardless of visibility, though. “Collapse” in the sense of “caving in” can happen to just a part of a

Probably not clearly recognisable to a British reporter regardless of visibility, though. “Collapse” in the sense of “caving in” can happen to just a part of a building. “Building 7 has collapsed” is shorthand for both “Building 7 has suffered a partial collapse” and “Building 7 is now a pile of rubble” - it’s not hard to understand that in the fog of what was a catastrophic event one is easily mistaken for the other, partially when the other is more “Get this on air now!” newsworthy.