I can't say for your experience. Mine, however includes a large and growing group of people who were treated like Public Enemy No. 1 on a routine traffic stop, who had no previous interactions with police.
When people who have done nothing more serious than 5 mph over the limit start getting treated as if they are fleeing a mass murder, the police aren't winning friends.
That said, most of the policemen I have met in 40+ years of driving and in other venues have been professional and courteous.
It is the exceptions (both good and bad but especially bad) who stand out in most people's minds and who make the news.
There are rules. We call those rules laws. Those laws are supposedly for everyone. Go by the rules and there is structure to the process. Don't go by the rules and mayhem can result.
Oh, and don't shoot the dog, he barks loud (that's his job), but he's a pussy cat.
95% of my interactions have been the same. I do have to say I've come across some really nice state patrol and city police.