Since February, RCI has been sailing in the USA with up to 10% unvaccinated passengers, which included kids (5 and up) and adults too. No wristbands either, so it was not possible to tell who was vaccinated and who was not as their very little restrictions onboard. The venue restrictions disappeared around the same time.
The only restriction I can think of, at the moment, was unvaccinated were not supposed to eat with vaccinated in the MDR if they weren’t part of the same traveling party. There was no such restriction for specialty dining or the WJ.