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)