You have quoted engineers, aka building designers, not fire fighters.
I have quoted the Society of
Fire Protection Engineers. I assume firefighters are familiar with their work.
I expect the fire chief did worry about this regarding WTC7, but recognized he could not prevent it without putting his crews in mortal danger.
I'd like to see some documentation of these worries. Certainly crews were put in mortal in danger in the towers. And I don't think they went in knowing there was a good chance the buildings would collapse. Their sense of urgency (and their courage) was devoted to getting as many people out alive as a possible before the fires got to them, not before the buildings collapsed, and not in an effort to prevent the collapses by quickly putting out the fires. I don't think total structural collapse was part of the strategy during those first couple of hours.
If you have some reporting to suggest otherwise, I'm all ears.
I'll grant that the thought of collapse might have occurred in the case of WTC7 after both towers failed.
But if the worry really was that the fires couldn't be allowed to burn out without undermining the structure, then I would have expected a lot of attention to be devoted to fighting those fires, preventing the collapse. There was no way to know (I imagine) exactly how much more chaos and destruction a third building collapse would cause. The best strategy would have been to make great efforts (including facing mortal danger) to prevent it.
I resent the assumption that firefighters haven't always striven to control s fire as quickly as possible.
I'm not sure what there is to resent in the idea that firefighting is always done with risk assessements and an evaluation of the likely costs and benefits of particular operations. As quickly "as possible" implies "under reasonable assumptions of risk". It's reasonable to risk your life to save the child in the bedroom, but perhaps not to save the child's favorite doll. Likewise, it's reasonable to risk your life to prevent the catastrophic collapse of a skyscraper in downtown Manhattan. But not to put out a fire that would burn out by itself without causing much more damage than it already had. A total building collapse, after all, is a mortal danger in its own right.
If you're a firefighter and are offended by this, please know that I am full of respect for the work firefighters do, and very aware of the dangers they face. I just assume they have their priorities straight.
And it seems to me that the events of 9/11 taught them something about the possible dangers, and this has reordered some of their priorities. That seems perfectly natural to me.