I favor the big picture theory, looking at some of the trends outside of golf design, which probably has never been a leader in design trends. I would have liked to see some 50's style huge tail fin equivalents in golf design, though!
I sense the 50's and the move to suburbia was also about bringing golf to the middle classes. They probably had enough of the fancy country clubs for the wealthy, which filled back up, but guys like Dedman were looking for ways to bring that generalized experience down to the middle class, in an affordable way (much like suburban houses were miniature versions of English estates)
In essence, many compromises were made to make that happen in a cost effective way. If machinery is a culprit, I think its maintenance machinery. Remember, one of the dominant trends heading into the shutdown was the RB Harris thing of two man maintenance, and that idea came out of the other end of WWII as well, IMHO. As new machinery, like bunker rakes, came on the market, bunkers responded primarily to these, (i.e. boobs and butts that were easy to machine rake) rather than any Golden Rule of Aesthetic proportion. Ditto riding greens mowers which required 8' to turn around.
Looked at in the vein of finally making golf affordable and available to the middle class, and that most of us here got our start in golf as a result, maybe we can forgive the architecture of the period at least a little bit! It truly was design for the times, IMHO, as per a recent thread I started.