A plot device is a narrative technique, object, or event in storytelling designed to move the story forward, initiate action, or resolve dilemmas. Effective devices arise naturally, while poor ones feel contrived. Common examples include the MacGuffin (object pursued, like in LOTR), cliffhangers, and red herrings.
This is the definition given to people to vulgarize narration. It's technically not usefull. As everything in a story is designed to move the plot forward. When we analyze, it's better to be precise about what is a problem since these elements are usually contextual.
For example, the fear of a character, which is a plot device, can be used for good narration BUT also can be used for bad narration. As such critics have to always be contextual and never absolute like what you guyz are doing.
Furthermore.
The way a device is used and feel "organic" is not absolute either. For example depending on your age, experience and knowledge of storytelling, you could experiment the same story twice very differently. As such, what feels organic to you, is not what feels organic to me. In fact it goes even beyond that. What "feel's organic" is ALSO a social construct and can become a cultural trait. The way we experience story in the west can sometimes feel inorganic to someone in other culture and hegemonies.
Your taste, your vision of the world, the way you enjoy stories,
all of this is socially constructed
So when I'm telling you that your "hate" is not a simple opinion but the result of a large system of beliefs relative to larger systems of beliefs relative to this current environment but also part of the fanbase. I'm showing you a critical approach of the analyzis of your taste on storytelling.
And it also applies on my taste too. My love of the story is also socially constructed. But this one is closer to the actual reality of what the story really is and what Oda really represents. While it's impossible to say "this is better than that", it's possible to objectively analyze the story within a cultural reference frame, in this case, the manga industry and odyssey stories in general.
Which means that I don't simply "love" the story, I know why it's good based on the devices and situations presented. Devices that I learn to understand and analyze and devices that you are ignoring or fallaciousely trying to convey as "bad" because you try to impose a fallacious vision of storytelling on this story.
A story is a large context. By creating illegitimate expectations, like "Luffy should not hold on against Imu". You remove yourself from the experience of the story and focus on a potential future element while ignoring his potential future contextuality. As such, if said situation comes by, your confirmation bias will kick in and prevent you from apprehending the entire contextuality of the situation.
In other word, you will only see what you know shouldn't have happened,
and you will be blind to the reasons why it actually make sense.
Meaning that if you create illegitimate expectations, and by "illegitimate", I mean expectations that are not based on setup or preparations for the story, or something "promised" to you....
Well you risk to be dissapointed at every turns and you will eventually create hatred for the Story you loved.