Wort contains a wide range of sugars, from glucose and sucrose to maltose and maltotriose, as well as dextrins.
Beer yeast comes in different varieties, some of which have a high attenuation (i.e. they ferment the beer out to a lower final gravity) while others have a low attenuation (they ferment out the beer out to a higher final gravity). The difference in attenuation is mainly the amount of maltotriose they are capable of fermenting. Dextrins are, to all intents and purposes, unfermentable for any regular beer yeast.
Wine is different. It contains almost exclusively fruit sugars, which the wine yeast ferments out almost completely, so there are few residual sugars to provide too much sweetness. (Sweet wines are an exception; these are either only partially fermented and the vintner stops the fermentation at the desired point, or they are back-sweetened.) Wine yeast also produces some additional acidity (on top of the acidity already provided by the fruit) as well as some spicy phenols, which help balance out any sweet notes (mostly fruity esters in wine) and "round out" the palate.
Some ciders are brewed with a modest amount of hops, though, although this is not too common.