You are correct that the adverse media coverage adds a factor that can’t even be calculated. It is safe to assume, IMO, that the numbers of those that feel like you probably have increased by at least 7 figures.
I’ve done Carnival in the Caribbean for 4 days back in the 90’s, i.e. pre-supership days. My wife and I are actively considering an Alaska cruise, too, but Carnival was not on our list of lines, this situation has only reinforced that choice.
...there vill be delousing