Really young carrots are also high in terpenoids. So I suppose another theory would be that the industrial farmers found a way to achieve larger sizes more rapidly, and are now harvesting too early because they can.

if I had more expendable income I would commission a study on this from you both!

I don't put that past agro-industrialists. But, I have had more experience with spoiled food from in-store shopping since COVID than before, and we know there has been a marked shift in how people shop (if at all) and eat, which the supply chains haven't sorted.