French roast is not a coffee but how the coffee is processed. French Roast is near burned coffee. The darker a coffee is roasted, the more the oils in the coffee are brought to the surface. the more the bean is turned into charcoal and the less it matters what the quality of the coffee being roasted is. In short, With French and other dark roasts, it's the roasting that gives the dominant flavor not the coffee beans that are roasted. Charcoal is Charcoal which may explain why so many coffee sellers roast their coffee very dark. They can buy cheap Brazilian coffee and sell it to the unsuspecting at high prices. Any variety of coffee be it Sumatran, Kenyan, Columbian, Kona, etc can be roasted any way a buyer wants. If you want to actually taste the varietal coffee, a lighter roast is the way to go.

FWIW, I'm a retired Kona Coffee Farmer.