𓊝 || 𝘸𝘩𝘺 𝘐 𝘏𝘈𝘛𝘌 𝘵𝘩𝘦 𝘪𝘥𝘦𝘢 𝘰𝘧 𝘑𝘢𝘴. 𝘏𝘰𝘰𝘬 𝘣𝘦𝘪𝘯𝘨 𝘢 "𝘩𝘦𝘳𝘰"
DISCLAIMER: I'm not hating on anyone's personal headcanons and/or opinions, HOWEVER this trope has never been done correctly, and it inherently is really difficult to do so due to his character on an inherent level.
I first (as I always do when it comes to Jas. Hook and Peter Pan as a general story), blame Disney and the lack of perspective.
People have a narrow-minded way of assuming that JUST because a protagonist is not all "good," that the antagonist must therefore be "better" than them and therefore the "hero." This, of course, removes all depth from every story and is a problem for more media than just Peter Pan; however, Disney is also largely responsible for this. They are responsible for Jas. Hook being viewed almost entirely as comical, which makes him seem more easily sympathized with and therefore softened.
Peter Pan is a bratty, entitled snob, who is canonically selfish and truly uncaring of the well-being of others, even swinging birds to their death and stealing their food in the book (of course, like no adaptations show this). So it is completely reasonable, IMO, to see him as a villain; HOWEVER, it gets very unreasonable to start viewing Jas. Hook as hero beyond this point.
People also like taking contrarian viewpoints purely to be 'quirky,' even if it doesn't make sense whatsoever. Now, keep in mind, this is not me saying AUs are invalid and you're not allowed to make them; this is me talking about those who truly view Jas. Hook as a hero as some sort of reactionary sentiment against Peter Pan.
Jas. Hook is very much NOT a hero; it is debatable if he is truly a villain, but for simplicity, he is, as he is opposed to the protagonist, which is the basic key to being certified a villain. Unlike many other fairytales, Jas. Hook has depth; he isn't entirely malicious or evil like many other fairytales, he has a reasonable motive for why he hates Peter Pan. Where he gets more villainous is when he is unnecessarily cruel to children simply because they're associated with Pan (and also because he hates children).
People tend to forget that Jas. Hook hates children, often implying he secretly has some sort of soft spot for them or at least wants them to escape the clutches of Peter?? This is ridiculous because Hook is more than willing to make children walk the plank and even whip them with no motive besides to kill/harm them.
Any instance of Hook being "kind" to children is manipulation. (kinda breaks my heart because the idea of Hook being kind to children is one I personally favor)
Now, why is this such a popular narrative?? Because of AUs, which I have no problem with, and illiterate YouTube theorists.
A lot of theory-oriented channels around the mid-to-late 2010s had a penchant for the idea of "hero Jas. Hook", and generally just the idea of evil Peter Pan (which is reasonable), and my least favorite, "everyone is dead wooo!!111"
I hate that theory because it strips the whimsy of the story and makes it unnecessarily dark. Modern people today have an obsession with twisting children's fairy tales due to a lack of original ideas in media; however, that's a different subject. It doesn't need to be said that JAS. HOOK IS AN EVIL MAN. But that's ok with me.
People don't like enjoying characters that are contradictory to their morality, which is why they tend to soften them and downplay their villainy through elaborate headcanons or denial. It's only human at the end of the day, but this humanity leads to severe mischaracterization.