Motorists running red lights, speeding up for amber lights, exceeding the speed limits, tailgating, dangerously overtaking and so on, is all so common as to be unnoteworthy. This doesn't justify cyclists running reds, but it should put it into perspective.
I don't think I've ever heard of a cyclist getting mad at another cyclist for stopping at a red light. The propensity to violate traffic laws seems to be higher among drivers than cyclists.
That’s because it’s assumed that it’s OK to run yellow lights. The meme goes “yellow - step on it!” And in this way cars do run red lights, it’s just that they get through much faster. They know they’re supposed to slow down for the yellow. They have enough stopping distance when it turns yellow. And they still drive fast to skip the red light. I observe this behavior all the time driving my car. I slow and stop for yellow, but the other lane speeds through.