I think the issues is driver awareness. The driver should be aware that they are impeding ttaffic and do what they can to improve traffic flow vs. being oblivious to the fact that there is a line of traffic behind them.
In some cases a pull off maybe available in some cases there maybe no way to allow the traffic to pass.
However the offending driver will never find a pull off if they are aware they are impeding traffic and not looking for a way to let the traffic pass.
A good driver will be aware and couteous vs. unaware or stubborn.
Often the driver does not believe they are impeding trafic or they believe it is OK for them to impede traffic regardless of the situation.