I have three decades in the wine and booze industry. I have worked it at all levels in the USA. This is the biggest load of unscientific horseshit imaginable.
Terroir is the notion that the climate and surrounding conditions can impart specific unique flavors to grapes grown in a specific place. The grapes part is key because grapes, unlike many other plants, can make wine just using itself and maybe some water. The idea that wine barrels, whose trees come from places like the USA rather than this specific three hectare area in Ohio, can have a sense of terroir is laughable.
Yes American oak and French oak have different tastes but it isn't as if I could put a glass of whiskey in from of an expert and have them guess where the wood came from whereas doing so is a common test for grapes in wine.