is one piece episode 770 filler?

Luffy and the Straw Hats get excited upon discovering that they can reach Laugh Tale and the One Piece with the Road Poneglyphs, and Luffy races off to rescue Sanji and find the other Road Poneglyphs. His crewmates stop him, but Nekomamushi states that Luffy's plan will lead him to them, because two of the Road Poneglyphs are in the possession of the Emperors Big Mom and Kaidou.

The Straw Hats are appalled to hear this, though Luffy takes it in stride, as he planned on beating the Emperors anyway.