There are real costs to everyone involved if a small vocal minority gets carried away with naivety.
In the last 2-3 years, cruise ships - at least, the mainstream ones - have been been either kicked out of or severely limited in places such as Venice, Bora Bora, Key West, Norway, Cayman Islands, etc Or asked to port well out of town - hours away sometimes.
Princess and HAL got caught dumping in Alaskan waters, and their parent company has been flirting with bankruptcy all year long. Or, why do we think cruising was at the bottom of the re-opening priority list?
That said, good for the environment = good for bottom line too? RCL's Icon class is LNG-based. MSC's World class is LNG-based. Disney's Triton class is LNG-based. Even Carnival's new ships are. Clearly, cruise lines agree. More fuel efficient, lower maintenance, higher profit margin, AND better for the environment.
Apparently, "paper navigators are a cost-cutting measure." "Nothing to do with the environment." Very well. This year, we have spent 34 nights on DCL for less than the cost of maybe 20 in 2019. Almost 40% cheaper - on mostly packed sailings. Some Omicron, some war - but plenty of cost cutting. So, if cost cutting was my thing, I would let it be my thing.