The death of the small town seems like it was fore-ordained by simple economics. In big cities, you can afford to have businesses like restaurants that aren't Sysco retail outlets, movie theaters that show more than the five most popular films on Earth at the moment, libraries that have books beyond romance novels, bestsellers, and out-of-date nonfiction.
Moreover, cities are the economic drivers, even in the agricultural world:
https://www.zompist.com/jacobs.html
> But don't cities arise from and depend on agriculture? No: all economic progress originates in cities, [Jane] Jacobs tells us; and cheekily adds that all agricultural progress originates in cities. Great advances, such as mechanical reapers and electricity, were invented and adopted in or near cities before being applied to agricultural regions farther out. Productivity improvements in agriculture always begin near the cities and spread out.
> What we think of as purely rural activities often began in the cities. In premodern Europe, the quintessential cottage industry was weaving; but before cloth was woven in cottages the art was rediscovered and practiced in cities. Dark Ages peasants lived on gruel; the art of breadmaking was recovered first in cities (and based on city-grown bread; a medieval city had its own fields). In our own rural areas there are vast ranches where animals are fattened before slaughter; they are transplants from the city stockyards of Kansas City and Chicago.
> Driving the nail in the coffin of the spontaneous generation of cities from farmland, Jacobs describes the inability of Ireland to turn itself around after the disastrous famines of the 1840s:
>>
There were no ports to receive relief food... There were no mills for grinding relief grain. There were no mechanics or tools and equipment to build mills. There were no ovens for baking bread. There were no ways to spread information about how to grow crops other than potatoes. There was no way to distribute the seeds of other crops, nor to supply the farm tools that were indispensable for a change of crops...
>> To be sure, the Irish had reached this pass because they were held in an iron economic and social subjection. But the very core of that subjection-- and the reason why it was so effective and had rendered them so helpless-- was the systematic suppression of city industry, the same suppression in principle that the English had unsuccessfully tried to enforce upon industry in the little cities of the American colonies.
> Closer to home, here's a report from one Henry Grady, speaking in 1880 about a funeral in Pickens Co. Georgia, some years before.
>> The grave was dug through solid marble, but the marble headstone came from Vermont. It was in a pine wilderness but the pine coffin came from Cincinnati. An iron mountain over-shadowed it but the coffin nails and the screws and the shovel came from Pittsburgh. With hard wood and metal abounding, the corpse was hauled on a wagon from South Bend, Indiana. A hickory grove grew near by, but the pick and shovel handles came from New York. The cotton shirt on the dead man came from Cincinnati, the coat and breeches from Chicago, the shoes from Boston; the folded hands were encased in white gloves from New York... That country, so rich in undeveloped resources, furnished nothing for the funeral except the corpse and the hole in the ground and would probably have imported both of those if it could have done so.
> Grady is eloquently describing the circumstances of a passive economic region: despite all its resources, it makes nothing.
So blaming it all on Nixon, which has an obvious appeal I admit, is a bit ahistorical.