Cruise ship passengers provide a huge amount of revenue to the DR.That is not true, there are many more people out there other than you that want a snowbird visa. If you go to other social media sites this topic is discussed a lot. IMO it will happen, don't know when, but it will happen. I am confused by your comment of "revenue taken in at AI resorts via cruise ship passengers". You are saying cruise ship passengers are staying at AI resorts? I do not think that is correct.
AI resorts provide a huge amount of revenue to the DR.
(Cruise ship passengers don't stay at AI resorts....)
The revenue provided by illegal overstayers on tourist cards is a drop in the ocean compared to either one of the above and miniscule if you add them both up.
(Those who think illegal overstayers are of great importance are in the same category as those who said Sosua would disappear if the whoremonger sex tourists stopped coming . )