The original Love Boat did a lot of good for Princess. In fact, it was still doing it a lot of good when some teenaged executive decided old stuff was bad for business. People are still excited to meet the original cast members when they appear on a ship. Ted Lange did not need some wanna-be to remind people how much they loved Isaac. (One wonders what Gavin MacLeod would have made of the reality show.)
I have mentioned before the 2015 Princess Anniversary cruise on the Pacific Princess, two weeks repeating (modified) the Mexican itinerary from the old show. All of the original cast members were there, and Jack Jones sang the theme song at sail away. That cruise was sold out for literally years before it sailed, and those of us who were lucky enough to be there knew it was something special. (caribill has a great photo of the cast along with Sammy, the world's best Cruise Director.) I always wondered why Princess didn't use that cruise to advertise, but maybe the "new Princess" was already in someone's mind.
Well, that was then. This is now. Princess decided it didn't want to run on nostalgia (and the old people it attracted.) It seems their reality show stunt hasn't worked out, but I have faith that the "new Princess" can find something even worse to attract the demographic they really want.