I don't like Luffy's power being connected to Joyboy.
I don't like Luffy's power being reworked into something else.
I don't like the entire identity of the protagonist changing after 25 years of serialization.
I don't like that the current enemy may be defeated because of "fate" and a last-minute powerup.
I have to disagree with you here, hate it all you wish but this has been in works since chapter one, it's not like Oda dragged it suddenly out of his ass. He kept it quiet and dropped hints of it throughout the series. The minute Oda showed Roger starting a Pirate age, we pen 12 years later to Luffy already wanting to become a pirate king, ate the fruit and waited 10 years to set out. The series literally rubbed Luffy on us. Look at how he recruited talented crews, how he was great at judging people, how he helped people before entering the Grand Line.
When Luffy survived the execution attampt, Smoker was shocked and stated that it was like some force is keeping him alive. He almost got caught but got saved by his father. Afterwards Luffy always gets away from being caught or killed by a stroke of luck.
Woop Slap even question if this was fate, the narration before Dragon was revealed stated that the whole story begun long ago. It was clear that the series was going to end with a war, Oda even stated that in 1999.
Whiteboard announced that One Piece is real and someone is going to carry the burden. We pan to Luffy while this was happening.
Then we get Joyboy, and it has been hinted that he is going to play a role, a connection between them was bound to happen. Either Luffy is an reincarnation or Joyboy was his ancestor.
It may sound stupid but One Piece was meant to be an old fashioned story found in many fantasies such as fate, destiny, prophecies and chosen one, it has been what One Piece been all about.
Decidede, welcome to the reality of this series.