So this is a lively and interesting topic. Appreciate all the dialog. One thing I see is very common; EVEYONE complains, yet no one does anything about it, with the caveat that it's someone else's responsibility.
Happens at my course all the time. One group gets slow and the whole course goes into gridlock. Marshall takes the 5th, while the course has people walking off in disgust. All levels of golf have it happen, and as evidenced here, people talk about 6-7 hour rounds without any repercussions.
Well here's the deal. This is a professional sport with a governing body. Said governing body needs to step in and grow a pair and simply state, here are the rules on this course and here are the times allotted to complete each hole. Only exception is if there is a ruling that takes time (which happens), and then the timing adjusts per hole through the field.
Heck, racing has timing loops with electronics set up all over the place. The PGA has all manner of electronics on course to chart the drivel that's put up on their web site so people can track driving distance and all the other stats that people obsess over. Well here's a new one; time to play a hole! Add that one in and start publishing how long it takes to play a hole for each round. I bet you that as more and more becomes know and we separate fact from fiction, it will become very obvious who the offenders really are. And then there will be an actual chance to address this.
Look, this is not an easy deal. But it has to start someplace. And people need to not only accept responsibility, but also be willing to dole out the punishment for the crimes.