The one big advantage to the warrior are 1) banners, which give the entire party a considerable stat boost, and 2) high solo DPS without having to depend on others to stack boons on you. These are hardly enough to make the warrior the end-all be-all class of th game, though.
^ This guy has been pushing this argument and has made this claim a lot with absolutely no proof. There is, however, tons of proof of warriors blowing through content faster than any other class.
Some classes can come close in ideal circumstances, but overall in most content, nothing beats a warrior.