you are absolutely right, but if you are not keeping pace with the group in front and lose ground they should be letting people through, i thing thats all most people want.Not really. For a two ball and players round 10 handicap and below- yes.
But you cannot determine the speed of play on the basis of an
"open" course.
Most courses now accept players of all standards. If a club takes the money from a 24 handicap player, then it can't expect a 3 hour round from him.
And if you are a member of such a club , then you are going to find many times being behind groups doing their best and not playing to your speed.
And if the club is busy, then there may be several such groups you come up behind.
But like coming up behind a slow line of cars on the road. Just got to be accepted most of the time if there's nowhere to go.
Many years ago, clubs limited paying players to 18 handicap( show certificate), mostly for this reason. But now things are different.