Don't disagree, but it has erroneous info posted.
This is what I’m seeing - it mentions passports:
Q:
What personal documents—including proof of citizenship—do I need to bring?
A:
In order to board the ship at the start of a cruise, all Guests must provide a valid government-issued photo ID. For certain international itineraries, you will also need to present a
valid passport and travel visa.
Passports If needed for your itinerary,
Disney Cruise Line requests that you provide your passport number
at least 75 days prior to the start of your vacation. Simply add the details to the Guest Information Form found in
My Online Check-In. You may also save your passport information in your profile to use for future cruises.
Please note: All travelers, including U.S. Citizens and all foreign nationals, are required to have a valid passport to enter or re-enter the United States by air.
Other Travel Documents When you arrive at the port terminal,
additional documents are required to start your cruise. Save time by using
My Online Check-In to complete these documents in advance. Please be sure to bring the completed Online Check-In Port Arrival Form with you to the ship.
To find a list of specific documents required for your itinerary, read the Passport & Travel Documentation guidelines in
My Reservations.
https://disneycruise.disney.go.com/faq/preparing-for-cruise/travel-documents/