Technologically, certainly and people who wonder if it is necessary miss an ultimate point. Having a game and hardware that can render several orders of magnitude more polygons for example doesn't just let us get away from having objects with obvious straight edges that we know are not actually straight edges. Additional detail provides improvements to a whole host of modern maladies such as animation irregularities (not bad animations but rather inherent problems of linear geometric transformation - the smaller the composite polygons the less any particular polygon needs to skew to complete a given transformation) to using precious memory space to store various texture maps designed to simulate surface texture.
Beyond the obvious stuff like that, it also allows games to be placed in more complex settings. Half-Life wouldn't have been half-life were it hamstrung by the spartan brush limit of predecessors as it simply wouldn't have been possible to construct a world that resembled a place people might work when the game starts to unravel after a few thousand brushes (A brush was Quake's word for an individual polygon of world geometry. For example, a simple doorway required three brushes and all that gets you is a hole in a wall).
What improvements in graphical technology offer is more options to developers and designers allowing for the possibility to more completely express a particular creative vision. As always, the mileage of any particular vision will vary.