Since that's easier and cheaper compared to making a full sequel from the ground up.(Just imagine how much coding they must do to port the existing assets and codes to the latest version of Unreal Engine.)
Kinda similar to the way they made Shenmue 2 by using Shenmue 1's assets alongside adding some new ones.
Kinda similar to the way they made Shenmue 2 by using Shenmue 1's assets alongside adding some new ones.