I did a 1-week Caribbean cruise with P&O in February 2023 and only the first night had a dress code of tuxedos/suits. Barbados was probably the best stop. It was my first cruise and I wouldn't do one again; I'm 38 and 95% of the other guests were over 60). It was a 3* room in a floating 5* hotel. I did enjoy the variety of restaurants onboard, and exploring (briefly) all the islands we stopped at. I booked excursions via P&O for almost every stop and they were really good - kayaking mangroves, climbing a mountain, snorkelling with turtles.
Crusie lines differ massively on their clientele. P&O are always going to be on the older side, especially out of the school holidays. You'll find a younger crowd on other lines like Royal Caribbean, Norwegian and MSC.
