I can disagree about being pulled over for the tail light. I have been pulled over for that. Its their job. The rest has to do with the way they train cops. Some intelligent people can overcome the "us vs. them" training. Consider every citizen a possible murderer. Be 100% vigilant all the time. They call the training para military, but the problem is that officers aren't at war, they are dealing with citizens.
It does NOT equal manslaughter though. Police are put in these situation. Given society the way its been an office has EVERY reason to be afraid for his life in ANY traffic stop. Thats why they can't be charged with manslaughter (realistically) but only reckless homicide as long as it was in the line of duty. First mistake the DA made was overcharging and not offering the alternative.
There is a line between where you are and where their training lies. Be vigilant, but use your damn noodle.