Surprisingly, I think it will help the cruise industry because many tourists that normally fly to Caribbean islands will not have "resorts" to go to and will start to experiment with cruising.
I think cruises will contain more sea days and less ports but the ships will step up their game to provide better activities on board ... if they're smart... The privately owned islands held by the cruise lines will become more prevalent and for some, a beach is a beach is a beach ...
We may see new ports spring up which would be good for some of the little islands who have not been big players in the cruise arena ...