storyteller
Superstar
One piece has always been a series about destiny and fate
Luffy been foreshadowed since loguetown that he is a special someone/chosen hero
Anyone bytching about spoilers clearly hasn't been paying attention to what this series was since the Loguetown Arc
There's been numerous showings that Luffy is the destined hero
From his dream, Shirley's prophecy , his similar look to Roger, WBs statement to BB, etc
No one missed the fate foreshadowing . People are trying to figure out how that element is gonna be implemented.
There's obviously a hero everyone's waiting for. That's obviously gonna wind up being Luffy since he's the protagonist. But it's how he gets there that theorize about. The debate is whether Luffy was predetermined from birth or whether he'll earn it. And I'd argue that there has been ample evidence for both to make sense.
Example: People mention the Will of D as proof that Luffy was born special. But Jaguar D Saul ain't Joyboy for damned sure. There have been hints that Vivi, Momo, Gol D, and plenty of others have special roles to play as well. Kaido thought HE was Joyboy. All of which can mean that Joyboy is more of a title than one individual that would be reincarnated.
But there's also things like the Sun God Nika and Luffy posing the exact same way. The lightning strike that saved Luffy. And a bunch of other lucky moments with "how could that be a coincidence" commentaries to support Luffy as a predestined figure. I think Oden's predictions seem like the biggest hint toward that (and one of Roger's crew asked if Luffy and his crew were the ones everyone had been waiting for at one point which is a good hint).
I agree that heads upset about the predestined angle are overdoing it. But the Naruto-style hero wasn't/isn't foregone. Oda loves subversion, so I always figured even if Luffy is a figure of destiny there'd be a twist to the formula. Luffy's whole concept of a pirate is someone who is free to do what they want. Freedom of choice and being bound by fate tend to be clashing themes. I just suspect that Oda would have a clever way to make Luffy both...like the D standing for candidates to inherit Joyboy's will, but the one who rises to that role still would have to earn the title or some ish.
Another example of "more than one path to the conclusion we know is coming" would be
How did Luffy wake up just now? Was it Joyboy possessing him, his devil fruit awakening, or is it some other explanation? I could make a narrative based case for each. DF awakening was the turning point of the BM fight and too many strong characters have shown that ability for Luffy not to have it. But there's also all the talk about ghosts in the fire festival, and Zunisha heard "Joyboy." Plus that'd leave the door open for other possessions like Zoro who also was implied as dead being possessed by the OG dragon slayer Ryuma so there's fun ish that Oda could toy with there.
Either way, the fun of narratives is that there are usually multiple directions an author can take. Heads being too dedicated to any one solution will wind up butthurt and complaining. Lit analysis and reading in general would be boring AF if every narrative moved in straight lines with themes.