Ironic, considering a lot of headcanon is being used to justify Kid's importance over Shanks or what he needs to do as a competitor for One Piece (which is nonexistant mind you, he will never have a crew or fleet to match Luffy's).
All you need to do is follow the narrative. The story is nearing some sort of end, yes, years from now still, but it still needs to end. Removing Luffy's contemporaries, who have only been painted as allies in every single scenario they've been in this story since Sabaody, makes sense, because they will never be actual competitors for One Piece.
But sure, lets assume all of what I said was complete bullshit (which you'll say to yourself, out of denial probably). Continue to ask yourself some questions/realize a few things then:
1. Why did Oda have Kid and Law contribute to BMs defeat together? If Kid is Luffy's equal, why didnt he fight BM alone? If thats the case, why are we treating Law's fate any different from Kid's here? We also act like Law's loss to Doflamingo made him an irrelevant character. He ended up topping Big Mom with Kid. Kid losing does not do anything to harm him as an ally, because thats what he is.
2. What is the authors intention of recreating vol 25 with vol 105 of the 4 current Yonko if NOT to highlight their importance in the story? Why not make Kid (or Law for that matter) a Yonko? Its very clear there has been an intention for years to make this the intended Yonko group
But yes, sure, the volume following this is supposed to have Kid, a secondary character, defeat one of these Yonko immediately succeding this volume. Just a reminder that he chose BUGGY of all people to be a Yonko, not Kid
3. Shanks and Buggy are literally Oda's favorite characters. This is a cold hard fact.
4. A stupid one but I shit you not: Next chapter falls on Shanks' birthday. Do you actually think Oda, king of birthdays, dates and coincidences, will make Shanks (one of his favorite characters) look bad on his birthday, IF next chalpter focuses on this fight?
And Im not even providing you all of the narrative reasons why Shanks cannot lose at this stage of the story. But ill give you just "some" of the chapters to review:
- 1
- 96
- 580
- 903
- 907
- 1054
It is not headcanon to understand this. It IS headcanon however to assume Kid's relevance has to do with competing for One Piece. Oda says he's important, it doesnt not mean he wont be for the EoS, as Luffy's ally, just as he was at Wano.