As a long-retired career naval officer and (expired) merchant mariner, I am also a frequent cruiser. Retired from the USN in 1993 and took first cruise with my wife in 2004. Now after a couple of dozen, with eight in the last 15 months, I have the same observations and perhaps some insight.
We have cruised on HAL, Carnival, RCL and Princess in the more distant past, then did four cruises on Celebrity from 2019-2022. Early last year we ‘discovered’ MSC Cruises and the last eight have been with that line.
Using MSC as an example, cruises offer a getaway that can be a low in cost as $420pp for a 7-night cruise from Port Canaveral. That includes lodging, all meals, assorted free beverages and lots of entertainment opportunities. Increase that to $755 and you add wifi and a premium drink package with unlimited non-alcoholic and 15 alcoholic drinks per day. I don’t believe there is anything else in the travel/hospitality industry that can match that.
Cruise lines select ports based, of course, on the obvious need for good maritime services for these large ships, but also on the geographic market area these ships will draw on. While many folks fly to distant cruise ports, the majority prefer to drive there. Airlines are pricey and limit your luggage, but cruise ships do not. Different clientele drive to NYC, Baltimore, Norfolk, Canaveral and Miami as East Coast ports, and Galveston adds another growing port to Tampa and New Orleans on the GOM.
MSC has just opened a the world’s largest cruise terminal in Miami, capable of handling three ships at one time, with 36,000 passengers debarking/embarking in a day. They are building a new terminal in Galveston, and will move the MSC SEASCAPE (170k tons, 5800+ pax) there later this year. Her sister ship SEASHORE has been based in PC and will be joined later this year by the GRANDIOSA (181k tons, 6300+ pax). These ships generally sail at, or close to, full capacity.
MSC just brought the new WORLD AMERICA (216K tons, 6,800 pax) to Miami. She is the second of that class, with four more coming. And MSC just announced the Constellation class as a follow-on, at 265k tons the largest cruise ships afloat.
As noted by the OP, how can this trend continue? Where will all the cruisers come from to feed this growing capacity? Is MSC, the largest shipping line in the world, misjudging the future of the cruise industry?
As a final bit, almost all the cruise lines have a “ship-within-a-ship” concept, with more upscale features. MSC has the ‘Yacht Club’ as the pinnacle of its four Experience Levels, and is the only cruise line to incorporate the concept as a closed, gated community on the ship. ON SEASHORE, with 5700 pax, the YC has a capacity of 300. Six of our eight MSC cruises have been in the YC, as are the next nine we have booked. The rest of the ship is frequently referred to as GenPop.
Sorry for the very long post.