One problem is that the prevailing wisdom for many decades, is that "old growth forests" were the desired goal. After a couple of fires in the late 90s-early 2000, that changed. It was found that fire actually causes a lot of the native plants to bear seeds, and re-germinate. The Flora is very much like down in Melbourne area: dense thickets of brush, oak trees, willow, and Eucalyptus, which was imported from Oz by the railroad barons to try to have a local source of material for rail ties. Wrong species, as the imported trees grow fast, but with a twisted grain, which makes them unsuitable. Very invasive species, and in some areas around San Diego, they dominate: fast growing, and nothing grows below them, much like a pine tree.
SanDiego region is very cut up with canyons, arroyos, small valleys that can go for a couple of miles, or a few hundred yards, and be very steep. With waist high brush, one has to try to find a game trail, or cut trail, always a hoot in 100 degree weather. A fire can jump across a canyon, , side to side, in a few seconds. I have friends that have lost houses this way. So, with triple canopy Eucalyptus, waist high brush, and steep hill sides, the only effective recourse is aerial assault of the fire, or to let it burn until it gets to a better location to fight it. Calfire has instituted a policy of only fighting fires where the home owners have cleared a defensible space around their property. A harsh choice, but for the greater good. IF a fire gets hold, you could have as little as 2-3 minutes to get out of your house, and save your own skin. very tough to leave a house knowing that everything in it could be gone in the next 30 minutes.
If you could be impacted, be prepared. pet containers, full gas, a "go bag", and pre pack. Airline carry on bags are ideal, as they can hold enough for a few days, and are easy to move.
I have been through this, but now live in Texas, where I am learning about Tornados.