True, especially in less-developed or stable countries where kidnap gangs are a real problem.
> it's not the cookie-cutter, mixed income, urban sprawl neighborhoods that are going to be set ablaze
It tends to be the dense, liminal, downtown areas that are set ablaze. Being well off certainly does help you get away from the fires.
But I think a lot of people dislike preppers because of the implication that this effort is a substitute for being involved in preventing the disaster in the first place - or, on the nuttier fringe, seemingly trying to accelerate it. Especially political involvement.
Remember, for many people having insecure accomodation, food supply, and access to medical care is everyday life.
(your advice page seems to be from the sensible wing of "preparedness", assigning sensible probabilities to risks)