Kingdom Hearts creator Tetsuya Nomura has declared that he's yet to decide whether he'll finish the long-running series prior to his retirement, so it's entirely possible future Kingdom Hearts games could be released without Nomura's involvement.
In an interview with YoungJump (for which we're using machine translation), Nomura says he "only [has] a few years left until [he retires]", and so he has to "decide whether to retire first or finish the series first".
He goes on to say that Kingdom Hearts 4, which was announced all the way back in April 2022, will be "a story that will be completed". It's not entirely clear whether Nomura means that Kingdom Hearts 4 won't end on a cliffhanger or that it will conclude the series as a whole.
With regards to Kingdom Hearts 4, Nomura says that he intends the upcoming game, as well as smartphone title Kingdom Hearts Missing-Link, to be a "reset".
Nomura says he wanted a reset after Kingdom Hearts 3, so he "appointed new writers and even made a new logo" so that new players who weren't familiar with the series would find it easier to play Kingdom Hearts 4.
He also gives some insight into his creative process with regards to the series as a whole, saying that although he's "had the idea of going in this direction" (i.e. the overall series direction) since the original Kingdom Hearts, but that if "something doesn't fit, I'll improvise on the spot".
According to Nomura, he also has documents pertaining to elements of the Kingdom Hearts series that haven't been explored or explained, and he "keeps that a secret". That would honestly explain a lot.
It's well worth reading the full YoungJump interview if you're a Tetsuya Nomura fan, as it goes into detail not only about Kingdom Hearts, but also about some of Nomura's other projects, including the Final Fantasy 7 remake trilogy.
Kingdom Hearts 4 still doesn't have a release date yet, unfortunately. Stay tuned for more info on this and all other things Kingdom Hearts-related.
