I am not a coffee historian or even very knowledgable, but I thought that light roasting is the more traditional (even ancient) way of making coffee and that the roasting has gotten darker over time. Not so?
"Ancient" coffee roasting was probably very uneven. The beans were often just roasted in a skillet over a fire, not unlike toasting pine nuts. If you've ever tried toasting pine nuts on a stove, you've gotta be very careful with the heat control and keep the nuts moving frequently, or else you'll have some that are still blonde and some that are bordering on burnt.