Not quite a current Ruby passenger, we went April 16th for a week and the change was happening at that point. At the very start of the cruise we all wore masks. Be it in the lift, walking through horizon court, or deck 7, and would take it off in the room, or outside. Then the CDC changed the rules 18th of April and whilst we was in LA on the 19th, and we was being told that masks were no longer required on buses and transportation. Then after that the passengers did not wear a mask as much. Lifts yes, but inside walking around it was about 20% mask wearing, 80% not.
MDR dining, we had any time dining and was in the davinci at 5pm and we waited about 15 mins for an unbooked table. Bottecelli we booked for a half past 8 table and got straight in. With the davinci we did notice there was a bit of unorganisation in the queueing at the entrance. No one knew which side was anytime waiting side, or the prebooked side; so we did see the staff trying to filter everyone through the right way, so people were not missing thier booked times.
When it comes to mask wearing you do what feels comfortable. For me I felt better wearing a mask on the lifts, and in the queue for leaving the ship, and making sure I had my sanitizer on me. When it comes to dinner in the MDR; if you do not have a show on, the later slots were no queue at all, where as 5pm was busy, so worth a though if you are alright eating later than usual.