In Dead Men Tell No Tales, when the trident is finally divided, every curse in the sea disappears. So, Will Turner doesn't have to be in the Flying Dutchman forever. But he remains heartless?
He has it back inside him.
Turner was cursed to be heartless and to be the Captain of the Flying Dutchman.
From William Turner Jr.'s wiki (paraphrased):
Jack used the hand of the unconscious Will to impale Jones' heart with his broken sword. This act not only defeated Jones, but gave Will eternal life by making him the new captain of the Flying Dutchman. Will's father cut out his son's heart and placed it in the Dead Man's Chest.
Years later Henry succeeded in destroying the Trident - thus ending all curses in the sea and freeing Will from the curse of the Dutchman. Returning to dry land once more, Will was reunited with Henry who gave him back his necklace.
Once the trident was broken, the curse was broken. He
- was able to come back to land
- lost the barnacles and sea-elements covering his body
- has his heart beating back inside him (otherwise he would just die)
- no longer commands the Flying Dutchman
- no longer survives underwater
Despite this not being directly showed in the movie, it seems like a reasonable interpretation. He is just a regular man now, and doesn't have a hollow chest (as he is no longer cursed).