I don’t have anything substantial to prove this idea, mainly just vibes from the last trailer. I think the rivalry between Samus and Sylux will unfold in the span of a trilogy and Samus’ adventure on Viewros will be only the beginning. How likely do you think is that Retro Studios and Nintendo made this not as a standalone but already thinking of a trilogy?
I think it will ultimately depend on Retro’s willingness to keep working on these games for another decade and a half, and what other franchises they can realistically tackle now DK is in EPD’s hands. I would instinctively start working on another Prime immediately now that the machine is properly greased and running, but who knows.