I watched a strawbale building demonstration 20 years ago where they torched a stuccoed strawbale structure that had no treatments: the fire reached over 2000°f and when it was cooled, they cut open the stawbales and showed the fire didn't burn the bale more than an inch deep. They really do not burn due to the lack of oxygen.

Water on the other hand can rot out a whole wall if it's not sealed.

Then you violated the building code. Regarding fire and arguably more importantly air tightness to prevent condensation and resulting water damage.

In attics its mandatory to do a blow out test where you create overpressure and search for air movement and leaks with a smoke machine.

Rule of thumb is outer walls wind tight, inside perimeter walls air tight. (Diffusion open)

People in construction know what they're doing and in general know what they're talking about.

Unfortunately, that excellently constructed home they spent so much effort on will still be sitting there in 5, 15, maybe 50 years from now. And all that time it's definitely not getting all it's proper maintenance, and will slowly be dropping in quality.

I doubt these buildings would go up hindenburg style, but after a decade or two of being lived in, fires will not be as easy to put out in a home like this.

Source: not a construction worker, but have worked in construction for a few years here and there and have been working with fire for several decades (and working to make fire safe to handle and trying to fireproof a couple garages)