Imma be honest since people are more reasonable on wg than any other site/app...oda fumbled the bag with alot of characters and we'll never know why :(
Big mom got absolutely wasted, even if she comes back its meaningless
Kaido got ruined in the last few chapters of the fight
Zoro...don't get me started, this arc was his arc in terms of the swordsmen environment, but no.
Sanji, the continous use of him and ladies ruins alot of tension but it help built robin so i'll let this slide
Luffy, oh my, g5, decent, not the best, just decent.
Tension went from a solid 9.5-10 and dropped to a 3 after the reptitive, defeat, defeat, defeat, defeat, defeat, oh but wait, now we win.
And lastly, the filler deaths definitely did it. after the summary of the whole arc we find out blank and blank died, oh nice, cool. like there deaths could've been shown more meaningfully instead of leaving us hanging for 20+ chapters and then revealing they died after everything.