No. They are talking solely about the buffet restaurant's evening service and not the main dining room.
In the past on Celebrity they had part of the buffet seating set aside for table service at the nightly casual dinner. Last time I used it, it was a blend of self-service and waiter service, sort of like a family steakhouse. But that was a few years ago so I don't know if they had upgraded it to full service. Regardless, it is gone now.
They are eliminating the table service only in the buffet. You will continue to have your waiters every night in the main dining room regardless of the dress code for that night.