Here's what the Carnival site says about unvaccinated guests getting off the ship (the original question that was asked). I don't personally know how "strict" they are being about it. I know when the bubble excursions were being required they were strict because I heard multiple people at guest services complaining about it as though they didn't know the rules before they got on board. I'm guessing no one has answered because it seems not a lot of unvaccinated adults are getting exemptions to cruise at all to even know if they're being strict.
Shore Excursions and Destination Requirements for Unvaccinated Guests
Unvaccinated guests age 12 and older cannot go ashore in the ports of call on their own and guests may only debark in the ports of call if booked on a Carnival tour. At the conclusion of the tour, guests are encouraged to return to the ship; however, they may also enjoy dining and shopping in the port facility area.
In the event you choose not to purchase a Carnival tour, unvaccinated guests will have to remain on board.
Unvaccinated children age 11 and under are not required to purchase a Carnival shore excursion and may go ashore with their vaccinated parents/guardians to enjoy independent sightseeing (see below for specific requirements for certain destinations).
If your cruise visits a private port of call, such as Half Moon Cay and Princess Cays, unvaccinated guests may go ashore on their own or purchase any of our tours.
We cannot guarantee that additional restrictions will not be imposed by local authorities in the destinations we visit.
Please review the destination requirements for unvaccinated guests in the ports of call listed below:
San Juan – Based on our agreement with the destination, guests will have to remain on board
Cartagena, Colombia – age 18 and older will have to remain on board
Grand Turk – age 16 and older will have to remain on board
Bermuda – age 12 and older will have to remain on board
Bonaire – age 12 and older will have to remain on board
Grand Cayman – age 12 and older will have to remain on board
St. Kitts – age 12 and older will have to remain on board
Tortola – age 12 and older will have to remain on board