On cruise ships? You betcha. No cell towers in the middle of the ocean.
Plus, the theory is you’re on the cruise to relax; how much relaxing can one do if they are still tied to their phone.
Most cruise ships I’ve been on the last 5 years have had “cellular at sea”. If you wanted to, you could use your phone as normal when at sea, and just pay international roaming charges. They always turn it off in port, so you’re stuck on other country’s service.
That was probably knocked out in this ship fire, not a priority to power from emergency engines like toilets and lights.