Ben,
Langford wrote his piece on golf in the Chicago District and noted that sand was not natural, and that maybe some other natural landforms should be used much more. The idea clearly didn't stick.
Also, the idea of building bunkers after a few years of play went the way of the dodo bird once first impression marketing became the norm, but some courses still tweak in similar ways over the years.
Guys like Ross didn't do much superfluous bunkering, given their legendary Scottish thrift. Mac and Tilly were less constrained and more into aesthetics until the depression taught them both the value of economy in bunkering, an attitude you can see reflected in my posts. I am sure there are some old gca types (like me....) looking at the new work from 1990 that used and lost a lot of visual only sand bunkers, and thinking the next gen of gca's are forgetting the lessons some learned in harder times.
When I first started in the biz (1977 in Chicago) all the courses we worked on had sand bunker remnants short off the tee and other places. I actually kind of liked them, especially where their shadow patterns highlighted other course features.
I used a lot of grass bunkers over the years. I recall one remodel where a good player lamented that sand bunkers were easier for him. I explained that grass bunkers were harder for low handicappers and sand bunkers were harder for high handicappers, and that was exactly why I used them so much.