is one piece episode 233 filler?

The episode starts off with Sanji and Chopper sailing back to the merry after failing to find Robin. Sanji questions if Robin not returning has something to do with what Aokiji told them about Robin.

They agree if she's ok she will eventually turn up at the Going Merry. The episode shifts to Luffy and Nami who learn that the Merry is irreparable.

Luffy and Nami refuse to accept it but they are informed that the "keel" of the ship has been damaged too bad to be repaired.