dhhdjbd I don't believe I've seen other people point this out before...
Private spaces are their own separate profiles, so it makes sense that they wouldn't inherit those restrictions from the parent user unless GrapheneOS extends the functionality. The developers are still busy with getting GrapheneOS ported to Android 16 now, but they have indicated that there's interest in adding more features to private space as well as support for multiple private spaces. I think it makes a lot of sense to support inheriting those restrictions, but not sure if it can be easily done.