User blog comment:Kogath/Monster Hunter: World Discussion/@comment-6050823-20180131052523/@comment-25083735-20180201020351

Every monster hunter game is always called "The new world." mh3 "The new world." mh4 "The new world,"  mhgen,  you get the point. They literally named all the first gen areas "Old" to clarify any confusion between the areas, rather than literally just giving them different names.