can talk back, and a plain ceiling grille shows neither. So “intercom” describes the broadcast function well enough. It does not confirm you could hold a conversation through it.
What would actually come through it? Fire instructions. Severe-weather guidance, like a tornado warning telling guests to move to an interior hallway. Directions to shelter in place, then later to evacuate.
Some properties lean on visual alerts too, so a room may pair a speaker with a strobe light for guests who can’t rely on sound. Again, the exact mix depends