A lot of the problem is with drivers who won't pass big rigs.
They just don't want to pass. I long ago gave up trying to majorly slow down when the dashed center line for passing is there. I can see for sometimes a half a mile or even 3/4 of a mile down a straight away and they won't pass. As soon as I see 1 or 2 cars back, starting to pass the first one behind me and also passing me, I will take my foot off the accelerator, sometimes brake a little and let them pass.
Now if a trucker comes up behind me, I will work diligently to let them pass. One because they usually will pass and two they are working for a living and need to get on down the road.
So many times I have a single car come up behind me and then just match my speed almost always staying 3-4 car lengths back, but they just won't pass. Then a 2nd, 3rd and maybe a 4th car comes up behind them. Now there is a line of cars behind me, and that mostly is not my fault.
When I have 4 or more cars behind me I will work hard to find a place to let them pass, or if a paved pullout is available I will pull over and stop, unless it is on a 6%-10% grade.
Another gripe is when a 1/2 or a mile long passing lane comes up. I quickly move over into the right and lane and drop my speed 5-10mph. However the cars behind me have NO sense of urgency. It sometimes takes them 15-30 seconds to realize there is a passing lane, then they pass slowly and maybe 2-3 other cars pass, but the rest are stuck because the passing lane ends. I have even had the 1st car that wouldn't pass when they could have earlier, still stay behind me, blocking others that would pass when a dashed line passing area is available.