LA, I was born there. With all that ocean off in the sunset direction you often get protracted sunsets with a lot of color. If there are clouds in a nice arrangement...oh yeah! It's optics, or something. Aided by SO2, SO3, CO, CO2, and countless molecules I can not spell but which can kill you. Provided the more usual 2000 foot high marine/smog layer is not in place.
However, I do believe the Saturation Slider was invoked here, and not a little bit. But what the heck, sometimes sunsets FEEL that way when they don't exactly LOOK that way.
That's Griffith Observatory, named after a guy who shot his wife. You don't see that kind of naming much anymore.
I shot at the beach on the same day and the saturation slider was not invoked on this image. Some clarity, tone curve and lens correction.... it was a special sky for sure.