I think Marvel's given up on all the Nuhumans that aren't Kamala Khan, Moon Girl or the kids in the Marvel Rising stuff.
As for the in hiding thing, I'm pretty sure keeping them off the board for now is exactly what it is, tbh. When Death of the Inhumans came out, I said this just seemed like nuking the current status quo because things hadn't quite worked out the way Marvel was planning, and that the ending seemed to gel with that. I'm betting when we see the Royals again it'll be a more traditional take once again.