Same here in San Diego. Green doesn’t mean “go” like on the drag strip. We get used to the line of cars making a left through amber-to-red left arrows in heavy traffic conditions as you stated.
However, I have witnessed individuals who will speed through a red left arrow while the intersection is somewhat clear of oncoming traffic only to narrowly hit someone. They usually speed up from further down the lane in hopes they will make it through, only to find they are going too fast and are committed to the action.
Of course, Cyber Liberty is right. There are those who will insist on their right-of-way (green light) even if it means flirting with disaster.
I always pretend I’m early to an IRS appointment when I’m driving...lol...
My brother used to always drive the left-turn like that, because he was confident nobody would drag race the light and clobber him. I think he’s since wised up. Haven’t seen him do it in decades.