They are still using quarantine cabins (writing from quarantine cabin on Radiance). We self-tested and self-reported to medical. The overall experience is not as bad as it was in the beginning of the start-up. I remember the stories of cold food and cardboard containers, this is not the case today.
Although we were removed to an oceanview on deck 4, we are able to order MDR menu items for dinner and wine 🙂
We have cruised frequently since the start-up and this is our first exposure to Covid so the odds are still small to contract it on board. Our exposure can be blamed on bus and train travel during a pre-cruise land tour.
Since both DH and I are positive our experience cannot answer the original OP question, just speaking to the subsequent comments on current practices.
Also - we tested negative before the land tour and tested negative before embarkation which were required by RCCL