I don't know that its a matter of the powers that be as much as a matter of economies of scale and technological progress. One man can cover 10 or 100 times as many acres as our ancestors could 100 years ago.You can negotiate better seed contracts and chemicals with more acreage. You can keep buying more land with more free cash flow (its not like stock, you can't buy 1 or 2 acres at a time, you have to buy 30, 60, 90 or more acres at a time). You can keep maintenance people on staff. You can keep your equipment running more and in the barn less. If you buy enough equipment from a manufacturer, you even start getting free "tester" equipment to use from them from time to time!The only thing really, really shafting small farmers was the estate tax, but that is/was satisfactory now.
It's not that hard to get over the limit in many parts of the country, especially with a home. And closely-held "small business" face the same problem as the farms. Often, the survivors have to sell the business or farm to pay the taxes (up to 48% rate) since the taxes must be paid in cash, but the assets in the estate aren't in liquid cash unless sold.
And alot of what is taxed in the estate tax has already been taxed through income taxes while you were living. Income from closely held businesses that is reinvested, the after-tax payments made on a mortgage, the cost of investments purchased, all are already taxed.