I was on Splendor for a TA crossing last year. It was our 20 year wedding anniversary so we decided to dress up a few nights. My husband wore a tux and I wore a sparkly outfit.
And it was so darling, as the cruise went on, other couples came up to us and said, “we brought formal wear and now that we see you guys wearing it, we will dress up also!” Some of the gentlemen even said, “I brought a bow tie but didn’t know if I would feel comfortable wearing it and now I plan to wear it.”
Well by the end of the cruise there were a lot of people dolled up.
It’s ABSOLUTELY not required and people looked elegant in whatever evening wear they chose within the after 6pm dress code.
I think because it was a TA, there was something epic about the journey. That said, on our upcoming Caribbean cruise on Mariner, we are going to stick with evening appropriate but not formal wear.
Bottom line - it depends on you and your itinerary to make it your best trip, and people do not judge. Just look elegant and comfortable and you will do just fine.