To be honest, I look at video games from any age as a 'flavor' so to speak. Think about going to a buffalo wings place, and they come out with a new flavor and you try it and fall in love with it, but every now and then you want that flavor you use to eat all the time and still do. Games are all various different styles and it's really rare that a game is such an improvement and similar enough that it warrants replacing the previous entry outright.