I'm trying to think of a project I've worked on where the course didn't grow in size during construction. I know at Winter Park it didn't because it physically couldn't, and its pretty damn good. I know at Dismal, Tom made a strong effort not to just go larger. But the others, everyone wants more ground to work with and more grass.
I'm not sure the ball can be blamed for the current size of our golf courses. I think its easier to design bigger. Easier to look impressive, to frame, to create views and back drops, to chase that "beauty" thing Tommy alluded to. Bigger is definitely easier, but is it truly more fun to play? In every case? Are we to quick to score a bigger course higher? Can hazards be placed where the options are more about the club used off the tee vs the direction we pick? Can greens be built smaller but set within a landscape where there are still options vs just using wide array of different approach angles? Is going bigger the default because its safer in this era of very few new courses?
Holding all other things equal (c.p.) bigger- having more room- typically offers more options and variety, and, therefore, is more fun than being confined. Not always, but most often.
To the extent that the major design features on large sites are properly scaled, the natural bias in favor of aesthetics would tend to drive evaluations accordingly.
A course that scores highly on the type and variety of shots it rewards offers holes that allow different angles and some that suggest shot placement to specific areas with shorter clubs; some, like Rawls #13, do both.
Smaller greens tend to limit options, and, as you well know, can pose serious maintenance problems. That's not to say that all greens should be large enough to site an average home. I like the concept of proportionality, and matching the green complex to the scale of the surrounds/backgrounds.
Going bigger is not a default, but a continuation of many things in human existence, and certainly in golf since its inception. I was looking at the history of North Berwick- West and the one constant is expansion. I am sure that we will buck the law of diminishing returns some day, but I doubt that the evolution of the game in this direction will be arrested any time soon.