In "Golf Has Never Failed Me" Ross was quoted about liking the wonderful possibilities of the bulldozer. If the old guys were alive later, they would have changed methods, to be sure, for cost reasons if nothing else.
Not sure exactly what a Ross course built with dozers would be like (although, it would be an interesting study to see what his last few courses looked like, since they had some dozers used)
Would they be like the old guard, not changing while others experimented, like a young RTJ? Or would they experiment themselves, building bigger lakes, etc.? Given Ross changed his bunker style at Seminole a bit to "keep up" (although I think not as much as originally surmised) and that his plan for Oakland Hills looked a lot like the one Jones implemented after his death, I think he would literally be trying to keep up with the Jones.
Not unlike current old guard guys are adopting some new wave trends, like jagged bunkering, internal contours popular, I would have to think they would have moved somewhat to modern design. And some factors, like need for irrigation storage, would drive it as much as design theory.
Of course, none of us can really channel the mind of the dead, so its all speculation. I do recall Pete Dye, who met Ross at the end of his life, figures Ross would have extended Pinehurst in length to keep up with distance technology......not sure if he got that from Ross, or just assumed it.