This is true, however when you consider the benefits of YC, a large majority can be achieved by getting the premier package on princess, regardless of cabin type.
So an interior cabin on Sun + Premier vs YC.. Well the only additional benefit of YC is your own sun deck and a butler. It depends on each person, we never used the butler and the sun deck is nice but it’s a sun deck.
Premier takes care of dining (unlimited speciality vs YC restaurant, id argue speciality is better), it takes care of reserved seating in theatres, it has the unlimited drinks, the wifi, room service etc.
Its interesting - I do enjoy YC but for me I have to go YC on an MSC ship, whereas I don’t have to go suite class on other ships because they offer far more in these lesser packages than MSC do.