Nobody in LA is going anywhere.
The *only* bugging out you're going to be able to do is *before* disaster, so leave early. Nobody mentioned the gubmint shutting down freeways, not that they'd have to as they'd be gridlocked.
I've seen people fleeing hurricanes. it's pointless, 8 hours in a car to go a few miles, and that was a place with actual freeways that work normally.
LA is a desert. Where would I bug out to on foot? Living off the land is a fools errand for all but a few. Even people that are good at it can starve or twist an ankle.