I'm a pedestrian in SF and disagree with this. I tend to walk anywhere between 4-8 miles per day, just as a matter of course, and I see dozens and dozens of cyclists. A significant number of them do not stop at red lights when traffic is light. A majority do not stop at stop signs. When it comes to stopping, cars are much more law-abiding (likely because the penalty is worse, not because of any desire to be safer). Many cyclists make unsafe turns; I've had a few close calls while walking. Many ride on the sidewalk. I even occasionally see a cyclist riding the wrong way on a one-way street (though most will move to the sidewalk instead of doing this, which is just as bad).

And if you want further proof, just read the list of bicycle fatalities in SF and see who is at fault. Most of the time it is the vehicle.

This point has nothing to do with whether or not the majority of cyclists are responsible and law-abiding. All it does is suggest that drivers are inattentive, and that the state is strongly biased toward drivers and wrongly backs them up when they kill someone.

I wouldn't say that most cyclists are irresponsible (more that they tend to take risks, risks which may actually be reasonable and acceptable), and I certainly don't believe that most cyclists are at fault when there's a fatality involving a car (quite the opposite). But suggesting that most cyclists habitually follow the rules of the road... that's just absurd in my experience.