The issue is no less with the unique varieties of hemp now extinct. As the hemp industry struggles to recover in North America, new equipment will be invented employing modern engineering. And though we've lost the know-how for handling the crop, people will learn new ways, it was always too labor intensive. The loss of these factors of hemp production, though unfortunate, is not dire. The loss of the germplasm, that's serious.
Plant breeding is a slow science.
It has taken decades, for instance, to develop kenaf varieties adapted to Texas. But like an old tome left in the elements, the message is badly degraded. Meanwhile, the eradication squads are rappelling down from helicopters. Currently in North America we must import certified hemp varieties from Europe. That puts us on a par with pre-1850 from a plant breeder's perspective.