Because it's not a "vast" difference.
Well, again, you're seeing a "vast" difference where there really isn't one. So that's coloring your whole way of thinking here. The course ratings aren't very different, and that's MUCH more likely to result in changes to scoring.
And, you don't get to see their notes, but you can essentially re-create them. They're just a bunch of numbers, many of which are empirical. You can measure the depth of bunkers, their proximity to greens, and stuff like that.
Which means they've probably done it correctly.
The problem with rules and laws is whether or not they can be enforced.
Imagine the scenes if people were asked to hand over their personal devices. It would cause more problems than it solved.
To me, the more worrying thing is that people are missing out on the experience of actually being there. It's not about the player, it's about the photographer. Really, who is interested in your shot of player x? Or your crappy picture of the Mona Lisa? It's just a pathetic quest for personal validation; I was there, so I must be important.... or at least, exist.
Why would the slope difference be so vast on the highlighted course setups?
Score records show an equal scoring average with over 7k rounds recorded.
I guess I'm not seeing the big picture in course ratings by the team who rated our course.
With out there notes, we have no idea how they reach these ratings.
I've looked at several other course ratings and there are courses which have similar differences.
So, I guess it's not uncommon.