To make a structure more fire resistant you have to get rid of soffit vents.
The heat from the outside will make the wooden materials inside the soffit/fascia/rafter cavity combust.
This has happened in prior fires even when the exterior materials are all stucco/metal/masonry.
The other factor is removing all shrubs, ornamental and large trees away from the building.
In the Paradise, CA fire almost all the houses had multiple huge trees within 10-15 feet of the houses. If the 100’ high tree hanging over your house ignites, most likely your house is going to burn too.
We had a house in Paradise and sold it a few years before that fire. A lot of people were proud to have trees blocking view from their street. You had to get a permit to remove a tree. I only thought what a fire would do to that city.
Ron Howard made a movie “Rebuilding Paradise”. I bought the DVD.
Removing vents causes other problems. They are there for a reason. They remove moisture, prevent mold, regulate temperature, lower energy costs, prevent roof damage.
They have vents that do not allow or restrict ember entry and vents that seal shut when it gets hot.
Even with Hardy board and other resistant materials, the underlay material can get hot enough to burn. Our neighbor’s house was metal clad and it burned.
Trees usually aren’t a huge problem as long as tree liter is removed, and there aren’t any ladder fuels. That may be a big if. Crown fires are rare, that is where the fire advances via tree top without any aid from the ground fuels.
Paradise just had too much vegetation period, but yes, the less the vegetation the better.
Still, we see many stand alone structures, Ralph’s grocery in Palusade, BOA in Palisades , K-Mart in Santa Rosa, fast food restaurants with little around them in the middle of a parking lot burn.
There are many variables, but that doesn’t mean you don’t do what you can.