It’s a question I’ve been asked for 30 years. Back in the early 2000s, pre-internet, we’d stand and watch a sharp, used tractor or combine sell for $200,000. We’d say, “Can these prices go any higher?

In late January I headed to Sidney, Iowa, for the Lawrence and Mary Lou Crom farm retirement auction. Being at an in-person sale with live bidding and rubbing elbows with other actual humans was like ...