The thing is that they aren't trying to reach a destination, they are reaching it, without any relevance to it. What is relevant is what is happening inside the boat, not the voyage. In fact the voyage only relevance is that it is a time limit. Any kind of time limit would do. Or should it call it a "Time Limit Arc" too?
Just because there is mention of something happening in an arc, doesn't mean that arc is "that thing arc".
Right now this is a "Battle Royal Game arc" that happens to be in a boat going to a destination. The Boat, the Destination and the Travel have 0 relevance, they are just side dishes.
Question, in One Piece was the Sea Train "arc" a Voyage "arc"? Because there was a Boat/Train and it was reaching a destination!
And Namek arc was it a voyage arc? There was a spaceship(in fact 2) and it was reaching a destination! Goku Voyage part of that arc was amazing, seeing him training in the Gravitational Chamber was such a great Voyage, such an atypical voyage
This is the problem of generalizing and conflating everything. Suddenly everything is anything.