Curse of the Black Pearl by far. The sequels are just that and I feel that they rely too much on the supernatural, they just don’t have the combination of reality with a touch of the supernatural that the original does.
I partially agree with you. Two and three kind of demanded more supernatural elements, given that they were required to extend the story and create a grand narrative stretching across three films.
Dead Man's Chest had to expand upon
Curse of the Black Pearl by necessity, and
At World's End had to then expand upon
Dead Man's Chest by arguably more necessity.
It's only when
On Stranger Tides and
Dead Men Tell No Tales enter the equation that I really feel that the supernatural aspects began to feel tiresome and cliché...and also watered down.
We never received any explanation as to why Blackbeard's sword could do what it did or how he could zombify other people. He just happens to have a sword that does thingy things, and he happens to have the means to zombify his officers because...reasons.
We also learn nothing about the Devil's Triangle and what kind of magic was lurking inside to cause sailors to fear it and to cause Salazar's crew to become "cursed." We don't even know what "cursed" really means this time. All we know is that some kind of red vapor does some kind of thingy thing and now Salazar and his men are...forced to live in the Triangle for eternity? Is that what it does? Is that the curse? As far as I can tell, becoming ghosts and looking the way they did seems to simply be a result of them having died. You know, you die and your ghost takes on the appearance of the way in which you died? They're not undead, right? Just straight up dead?
Right? So...does the Triangle trap them in some kind of crossroads between life and the afterlife? How does this then play into the duties of the
Flying Dutchman? Gosh, nothing made sense. He and his crew were still cool though...I guess that was the point. Spectacle and fun.
The original three all had in-depth explanations as to why things were the way they were, and it never felt like an exposition dump either. It wasn't just random, shallow spectacle the way it was in the fourth and fifth movies. There was a reason for it, and for the most part, I felt that it worked pretty well. And it still felt grounded to me, despite continually ramping up the scale. I will defend two and three. Any further stories after that could and should have toned it down (even more so than what
On Stranger Tides tried to do, I think).
Full disclosure: You still have your opinion. I'm not trying to argue with it, I'm just commenting on it.