My parents own one of the largest/oldest family run farms in their state. There are two ways they were able to do that:
Be younger than their neighbors. Don't get me wrong, they're getting up there in years, but all their neighboring farmers are old or dead. As the one farm in the area that doesn't have cash flow issues the old farmers give up and sell them the land at a reasonable price.
Act like a corporate farm. They don't have employees. My dad is the CEO and his brother and sister are each shareholders. They oversee the big picture and my older brother runs the day to day. They have an have accountants and lawyers on retainer. They use planting and harvesting contractors so they don't have any equipment.
I have gotten on them many times about making some changes away from monoculture but they don't know how and it is literally their livelyhood. They won't change anything as long as it works.