Paul,
Yes probably a mindset, but ability to see things (and not dead people....) sure varies among architects. At least, based on the 10-20 young men I have had work for me over the years. Very few can really see how a slope (general or detailed) can be used, or at least influence the design. It can be learned to a degree, but still its innate ability.
Its hard to explain, but one example from early in my career. I was out setting stakes for the 8th green at Lake Arrowhead in Wisconsin. I drew the plan the past winter (1979-80) and was working in the field. Killian and Nugent were pretty standard (like Press Maxwell) 2, 3 or 4 mounds behind the green. I think I had drawn 3, but when I set the stake out for the back left corner and it read on the transit as "Fill 14" when the others were more standard 5 or 6, it was a light bulb moment for me. I knew filling 14 feet wasn't going to look good, would require tree removal, etc. and it always stuck with me. When I do back mounds, or even the high point of the green, I make sure they favor the high side, and they have always look better.
Some never see it, even with experience. Or as my Dad used to say, some people have 20 years experience, and others have 1 year experience, 20 times over. It has to be part of how we are wired at birth to think. The typical (but not good designers) thought process for many people tends to be straight line, not assessing literally hundreds of options, based on what you see. Considering many options simultaneously is the root of creativity, as I see it, but many humans just don't have that ability.
In fact, many architects (including sometimes me on flat ground) do pull out old plans, going for a balance of holes, favored designs, etc. And, there is some merit to that, and it is very common. There is some balance over just using the land, as you want to design a unique (best if you follow the land) but balanced (usually better if you have a few preconceived ideas to place appropriately on featureless ground).
Some of it is mindset. Somewhere in my files, I have an old Rees Jones mass grading plan. I used to call them "spaceship plans" because they didn't really do a grading plan, they simply put an oval (tried to make it look 3D, hence the spaceship) indicating where they were going to pile fill for later shaping. Obviously, with that mindset, you are going to build over that site and figure it out later. To be fair to Rees and company, this was Wild Wing, a very flat site that had to be built mostly with fill (although I was always proud of how little earth moving just to dry out fairways I was able to do)
Many Donald Ross plans show similar thinking, also to be fair.... it really has been along time since architects truly "found holes" that required no earthmoving. I am fairly sure that even in Scotland, hilltops were flattened enough to make reasonable greens.