Why not? Because they were ruled by the Valyrian Freehold as vassals, making them have a higher tier when they didn't is just not gonna happen. Rhoyne doesn't make much sense, if anything it would be Volantis as they consider themselves the heirs to the Freehold so they would not be underneath the Rhonyar who never even ruled over those areas but were instead defeated by the Freehold whilst it owned Volantis. The Three Daughters only existed for a relatively short period of time before being dismantled so having it be the de jure empire in Robert's Rebellion would make no sense. Great Andalos is probably the only remotely plausible one as the original Pentoshi interbred with the old Andals in that area, but still they have vastly different cultures and religious beliefs. Braavos never once owned any land in Lorath and was hidden for much of it early life until it was revealed a century after its founding, Lorath was a very isolated part of the Freehold and after the Doom was left much on its own and not ruled b anyone else.
