It would be better labeled a "fruitiness" chart as the wines anywhere other than the bottom three are all completely dry, no residual sugar (I'm talking about the normal kinds). Cab is just as dry, e.g., low sugar, as zinfandel, though the latter tastes "fruitier" usually. Malbec is also dry and not very fruity either usually.
It makes no sense. The bottom three are quite sweet by design. Port is inherently high in sugar.
It's like claiming riesling is a sweet wine. It can be, the best ones are bone dry and very bracing. Wine is a multidimensional thing.
Most wines are fermented to dryness, meaning they have no/very little residual sugar. If you see an alcohol level of 8-9%, then it probably does have residual sugar.
