When most golf courses decided to make renovations in the years before the beginnings of the Second Golden Age (late 1980s and early 1990s), the changes seem to have been mostly about repairs (e.g. new sand traps because the old ones were 30 years old) or essentially about "dumbing down" the course (containment mounding, flat fairways, tree campaigns, bunker elimination, simpler greens). When it dawned upon Pete Dye that some of the pre-WW2 Golden Age golf courses were the designs of geniuses whose ideas had been lost (was it Pete Dye who was the first to realize this idea? If not, who was it?), the world set off on a new path in recovering/restoring those golf courses and building new ones based on the rediscovered principles. It was like the Renaissance rediscovery of Greek culture 1400 years later. On this topic, a great read: "The Swerve: How the World Became Modern."
Perhaps, the first and most fundamental problem that Golden Age designers were attempting to solve was whether an architect could design a golf course that served both high and low handicappers at the same time. Their solutions to this stubborn problem might have been one of the keys that unlocked the Golden Age. Most believed, then and now, that a golf course design could not really have it both ways: either it had to be designed for the top golfers (too hard for the average handicappers) or for the everyday golfers (too easy for the low handicappers).
In some ways, it still seems like we don't really quite believe that doing both is really quite possible. Maybe it's because of slope? We can rate a golf course's difficulty today so that handicaps will accurately equalize the highest number of matches between different levels of players. I know that's not quite the rationale or process, but we could assign slope with a mathematical model that solved for creating the highest number of even matches between golfers of varying abilities and it would demonstrate the relative difficulty of a golf course.
On another tangent, to rate the best courses, slope is obviously not the answer, or we could just rank courses by their slope. The best courses do seem to solve for the above mentioned design problem.
The other idea that I thought was interesting came from an article by Tom Simpson, and he actually gets it from Arthur Croome: the biggest hazard for the average golfer is in his own head. Don't play the low handicapper's game. Rather, think your way around a well-designed golf course. But again, this suggests that a golf course can be designed in a way that solves the fundamental problem.