There are circumstances for which I'd suggest a bike is a reasonable mobility tool. Say, after a major earthquake, where immediate hazards are few, fuel supplies are limited, mobility options few, and when the ability to pick up the bike or wheel it through areas where the roadbed is badly damaged or littered with debris would be a strong plus for a bicycle.
Having done quite a bit of cycling myself (multiple century and double-century rides -- miles, periods of 200-300+ mile weeks regulary, a 30+ mile round-trip commute, extensive tours), personal experience with much of the regions burnt by recent wildfires (I'd visited a friend in Chico fall of 2015, and drove out via the next highway north of Paradise, CA-32 to Lassen), with its mountainous terrain and very close-in forests (I was struck by how dry the region was three years ago, and was concerned at the time of what I'd do if a fire were to start), and been relatively close to smaller (though still multi-acre) wildfires, and watched footage of the Paradise evacuation, I would not want to rely on a bike to get me away from one under the circumstances prevailing for Paradise.
The timeline of the fire, warnings, alerts, and evacuation were short. The fire was massive and intense. Flames were immediately adjacent to if not on the roadbed. One of the factors disabling vehicles were tires exploding from heat. And the primary road out (Skyway) is not a constant descent -- there are up-and-down sections.
Cycling through that would simply be insane.
Flat terrain, a constant descent, ample warning: possibly.
Conditions of Paradise in November 2018: not a chance in the hell that it was.
