There really are people who don't give me time to react to the light change. I drive a manual. It takes time to clutch in, first gear, brake out, throttle in, clutch out. And don't get me started on inclines.
I sometimes have to go straight through a specific light (where 95% of traffic goes right) to get home. So I'm first in line waiting at the red. No turn signal because I'm crossing the road. A woman in an SUV sitting behind me gives a little honk. Then a few seconds pass and she starts laying on her horn. I had to reach up and out of my sunroof and point straight ahead to tell her I am going straight. Stopped honking after that.
Right on red is optional AND requires a full stop first. The amount of people that just roll right through without a stop like they have any right of way then get pissed when the cross traffic blasts by in front of them
I drive a manual sometimes and never really have a problem starting at a light. The real problem is being 4 cars back and the car in front of you starts to move 3 inches forward after the light has been green for 30 seconds then abruptly stops and you stall your car. It's great.