Crytek says that there is nothing stopping them from developing a sequel to Ryse. Ryse 2 could be developed, but it will not going into development till next-gen sales improve.
The rumors that Ryse 2 has been cancelled are not actual accurate. A better way to put it is that Crytek is waiting for the right timing to do a sequel. Crytek owns the Ryse IP and once the installed user base for the next-generation consoles is much higher they will look at it again.
One thing that many might find interesting is that since Crytek owns the Ryse IP, there is nothing in there current contract that would stop the developer from developing the Ryse sequel (Ryse 2) for the PlayStaiton 4 as well as the Xbox One should the project move forward at some point in the future.
Crytek has provided no hints on when they might revisit the possibility of a Ryse sequel, but they do admit that they have received a lot of positive feedback from players who would like to see Ryse 2.