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This isn't accurate at all. First, it did not collapse as it would have during a controlled demolition; the towers "flowered" outwards, spilling debris all around them, destroying other buildings in the process. A controlled demolition takes weeks or months to plan not because it is difficult to cause a building to collapse on itself, but because it is difficult to do so in a way that does damage nearby structures.
The phenomenon of progressive collapse is well documented. An interesting set of examples are those associated with a construction technique in which floors of a building are jacked into place. Even once secured adequately, the collapse of an upper floor-plate will cause progressive collapse as the lower floor-plate is not meant to support the floor above it. There is also the Sampoong collapse, a progressive collapse of a 5-story structure in precisely the same manner. As other examples there is the progressive collapse of the damaged sections of the Ronan Point tower (gas explosion at the 18th floor) and the damaged portion of the A P Murrah Federal Building (damaged by McVeigh).
It's hard to find progressive collapse examples for a very simple reason: it's easy to avoid unless the building sustains significant trauma high in the structure. Most terrorist attacks won't produce it, either, because they do not generally target high enough in the structure to cause it.
The issue with building number 7 wasn't that it caught fire, but that the magnitude of the disaster prevented the fire from being adequately addressed. No modern building, with the exception of some embassies and other hardened structures, is meant to stand alone with a fire raging on inside it. So, yes: without fire protection you're totally screwed. This is why a city like San Francisco, which faces a high disaster risk from earthquakes, built a seawater-flooded fire protection system after the last great quake. This also puts the lie to your claim: there are numerous collapses from sporadic fires, they're just not documented well because they tend to happen in the midst of disasters. If you've ever seen the rubble when a building burns down starting from a high floor, you'd know that they collapse. Hell, I'm sure you could YouTube it.