As for Luffy he has always been special and he has ALWAYS been presented as someone special far from the realm of the "hard working underdog".
1. First Luffy is the literal incarnation of Hope. He is presented as the character that we must BELIEVE in. Which is the OPPOSITE of an underdog. Literally, Luffy saves people.
2. Second, Luffy was not presented as a
real underdog until Crocodile appeared.
3. Luffy was FIRSTLY seen working on himself when he met Vivi. Up until this point, Luffy vibed with situation and didn't care about his own behavior or the state of his own strenght (
at least after his departure). The second time he had to work hard through himself was depicted through crocodile when he invented ways to beat him. The third time (if you do not take the bar fight which was a lesson learned back in the dayz) was against Enel, then it was against Aokiji where he later demonstrated against Blueno the need to become stronger for the FIRST time for his friends after
THINKING about a new technique he could come up with. (
yes i'm emphasizing the "thinking" part because people never really took care to look at these panels for what they really were. Not training, THINKING, COMING UP with something. Something he wanted to TRY)
This is what I'm talking when I say "subtle hints at gear 5", "subtle preparations". Luffy does not train. He does not "work hard" outside of battles and timeskip.
What he does is simply not giving up. Ever.
His techniques, his powers are mostly due to his brain, not his brawl. Luffy had to train for the first time since his youth because he lost to someone. Before that.. there are no data or too few to support this idea.
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What happened - I believed - is that during One Piece, you read Naruto, like me, probably liking more Naruto than One Piece at first, like me too. And you projected some of the thematics of Naruto
(or another manga) which are also the thematics of the meritocracy (
"big work, big reward") into the story without reflecting about it.
And you are now projecting the flaws of Naruto (
the sudden shift between work and destiny) on One Piece
Because when you tell me that "One Piece Started as a tale about an hard working underdog".. when we know that the D appeared as far as Drum as a mystery, that people started talking about Luffy has the reincarnation of Gol D Roger... or that characters spoke about
destiny as early as CHAPTER 96
And when we also witnessed THREE chapters later a freaking LIGHTNING STRIKE coming down out of seemingly nowhere to save Luffy!!
Leaving characters wondering about god:
I'm sorry but I will tell you straight in the eyes something that you need to hear to get a wake up call:
You do not understand what you are talking about the story.
One Piece is not the story of an "hard working underdog"
it is the tale of a legendary crew.
Probably written by someone long after the fact.