Look, "this person has written a fic about this" does not really make a good argument, because I am not commenting on a fanfic, I am commenting on a post. And that post, to me, kinda misunderstands and misconstrues why people complain about the specific ending.
And that is spoken as someone who absolutely adores AWE. It is my favorite movie out of the trilogy (and to me there is only a trilogy, there is no other two movies, those never existed, I ignore them, I hate them, they are shit). But I also do very much understand the frustration people have with the way the ending in regards to the Dutchman happens, how it affects Elizabeth specifically, and the romance in general, and also how the movies communicate the function of it all.
Because first of all: most people do not watch those movies dozens of times. Most people who online voice discontent with this ending have, at most, watched the movies maybe three times. Chances are, they actually only watched them once or twice. People who watch the movies again and again are the exception, not the rule. People who also consume commentary, artbooks, and other assorted stuff of the franchise are even rarer.
And first of all, the fact of the matter is: because DMC does not communicate the whole logic behind the curse very well, the moment it is brought up as a complication for the "who is the next captain" plot early in AWE feels very jarring for most people. Because the reason of why the Dutchman is cursed exactly is hinted at in DMC, but it is not explained, so when "oh, but what about not being able to go on land, that sure would suck" comes up in AWE it feels out of nowhere. I do remember the discussion on the movie when it came out - being in the fandom back then. This entire thing feeling jarring to many was a big reason for why in the first few years after AWE came out, a lot of people were like "Oh, this movie is so bad". Which was quite frustrating as a big AWE defender, but... I do by now somewhat get the frustration people had. I mean, while I liked the movie a lot back then (mostly for the worldbuilding and Davy Jones and for Elizabeth being fucking epic), but even I do know I complained a bunch about how it was not well set-up, even though I knew that it was a known fact to the people working on the movie when they worked on it, given the two movies were shot back-to-back, so the general plot was lined out before, even if some details likely will have changed, because no screenplay survives the actual shoot unchanged. But we also know from the cut scenes of DMC that there were two scenes that at least somewhat set up the 10 years part to a degree in a way the theatrical release did not.
But for the general movie going audience... people who saw it back then often would have just seen DMC in 2006, and then AWE a year later. DMC does not communicate the mechanic a whole lot, and someone who only saw DMC in cinema back then, and then AWE a year later... was understandibly lost. Even today, when someone binges the movies... The set up is not done well.
And, from the perspective of the general audience: the Will/Elizabeth romance was a big narrative core. And of course a lot of what DMC and AWE are is kind of a result of the general "CotBP was written as a standalone, but now we got to do two sequels, but we already had a happy end so what to do now?" thing. Which largely for Will and Elizabeth meant the movies had to throw a wrench into that happy end, because... well, back then it was common understanding that a blockbuster needed a secondary romantic conflict to carry stuff. So, yeah, they needed romantic tension and could not just have Will and Liz be in a stable relationship. There needed to be at least one driving romantic subplot. And due to this, well... a lot of people who are and were invested in it felt kinda cheated out of the happy end they thought they were guaranteed, and that by a plot mechanic that was really not well set-up, or in fact even explained that well even in AWE. To a lot of people it felt like "tragic for tragedy's sake". You can argue about the validity of that reading. I personally do think that yes, it was planned ahead, the lore was just not well-communicated, which likely has to do with it being very ambitious movies that also were a big investment, meaning that in the final cut there were hundreds of people who made decisions in what the movie was in the end and at times people who are bound in the process think something is obvious that for the end viewer it is not.
Again: the average person reacting to a movie has not seen that movie more than three times, if even that often.
But lastly, well... Look, my personal head canon is also that Elizabeth spent those ten years having all sorts of adventures as a pirate and being fucking badass. But, I sadly also am a person who has been forced to do all the media analysis thing. And if a character has a big scene where they say good-bye to every other character, and then are last scene staring longingly at the sea, and then only have one more scene - a post credit scene - where they are still staring longingly at the sea 10 years later, what the movie communicates with this is: "This character has now spent 10 years staring at this sea." And, well, in the most charitable reading of the intentions of whoever made the decision to have this, it is because they were very aware of Elizabeth being the main character, and the traditional hero's journey (which is still being used as a blueprint in Hollywood as it is the baseline for the "Save the Cat" beatsheet that about 90% of all Hollywood movies are forced to adhere to, no matter how fucking bullshit that is) the hero does eventually return home being changed. So, the nice reading that does not assume "this is misogynist bullcrap" is "Liz is the hero and as such should return home". The, in my view, more likely truth behind it all is more along the lines of: "Some suit at some point late in development made the decision that ending a movie on a woman being empowered was not a thing you could do in 2007, so fuck everything the movies have done with this character to this point, she is gonna be good woman doing good womanly things like waiting on the shore for her hero and being a mom."
Like, again, I do not agree with this. I think it is bullshit. I think it is being untrue to both the story of the trilogy and the characters in question. But I also cannot look at what the movie presents - especially with the big "good bye" - and conclude that "actually the movie wanted to communicate that obviously she spent 10 years being the Pirate King and only returned to that shore with the kid to say hi to Will when he came back".
Again: in my headcanon that is also what happened. She was a pirate king and had a bunch of awesome adventures during those 10 years. Because her waiting at the shore is bullshit and always was bullshit.
But it also is what the movie does communicate based on how it sets her going to shore up, and how it frames it, especially given that the movie exists in the context of other media which always gave the baseline for a woman to, well, do that.
I hate this, yes. I headcanon it away as well. I think headcanoning it away is reasonable. But I also do know that a lot of people talking about those movies do not have elaborate headcanons, or have watched the movie a whole lot, or are even aware of deleted scenes, or the books, or really anything existing. Most people watch the movie once, and go "Well, the romance ending like that felt kinda unsatisfying" and "Elizabeth's story ending like this felt unfitting for it", and then they post it, and then that's about it.
And while I would agree that the people complaining that "why did Jack not say he was cursed all the time?" clearly did not pay attention in CotBP. I do think that people complaining about the mechanics of the Dutchman do have more of a leg to stand on. Because I do agree with them that the explanation is given in a convoluted manner, and also comes in too late to feel satisfying as a complication for the happy end.