I have told this story before, but I recall searching for places to play around Chicago, when in my teens, and some courses touted "professionally designed with elevated greens!" I took that to mean they weren't a farmer built, moved to little earth, small circle greens kind of course that you could find anywhere.
As Mark alludes, raising greens became more or less standard way before WWII and they made sense, as they relied (and we still do) on surface drainage. There is little drainage risk if you raise green complexes, and some if you leave them at ground level. Other benefits include better bunker depth and visibility, as bunkers sunk below grade are hard to see in most cases. It tends to make the green itself more prominent, as most of us believe it should be, as the ultimate target on the hole.
On a slope of any kind, it's sort of hard to define what is elevated. If there are ten feet of fall on the natural green site, I always tended to set the middle of the green right in between. The biggest reason is that it is easiest to balance cut and fill that way, without hauling in additional dirt. Since the green only needs to slope 2-3 feet on that site, that means the front tends to be 3-4 feet above the original grade, as does the back. Is that green elevated 3-4 feet (front measure) or on grade (middle measure?)
Yes, there are some flat, floodplain sites that just require you to elevate the green with hauled fill. I think those are the kind the OP is talking about, and that others object to, but they are sometimes necessary. And, Wilson and RTJ seemingly (although I bet if you looked at their entire portfolios, it wouldn't be as dramatic as we assume) tended to elevate all greens for reasons above, and difficulty. By the time I started my biz, everyone was working away from that trend towards CCFAD playability. It's a pretty simple equation really, the higher the green, the more difficult to hit and recover from around the green.
Earlier in my career, I was really too focused, perhaps, on building greens that cut and fill balanced on site. After redoing Wilson's La Costa, I fell back in like with the idea of the gently running upslope approach, albeit, trying to expand the design hazard vocabulary away from merely sand bunkers. And, as with everything else golf design related, too much of anything repeated is not great, and what is wrong with an eclectic approach where all greens are different heights above the fw? Nature usually suggests that anyway.