I'm not a video game developer, but from a business perspective, it would make sense that Square Enix would instead focus on one major title at a time. 2023 is going to be the year of Final Fantasy. We know that 16 is releasing in late June 2023, and Final Fantasy 7 Rebirth will be sometime between October 2023-March 2024, so Kingdom Hearts 4 will not be released in either window.
If I was a betting man, I'd say that Kingdom Hearts 4 is further along in development than some people are expecting. It already has completed combat scenarios and voice acting, which KH3 didn't have when its first teasers were unveiled. A big part of the reason KH3 took so long is that they had to build all the assets from scratch and switched engines a couple of times. Further, development was hampered because Square's teams were spread too thin.
With FF16 and FF7Rebirth all having different directors, it stands to reason that KH4's development is not likely to be as prolonged. Tetsuya Nomura is probably devoting most of his energy to Missing Link and KH4 at this point.
With news of a closed beta for Missing Link, we can safely assume that game is probably getting closer to release. Likely, sometime in mid-2023.
What does this mean for KH4? It further reduces the amount of workload the teams at Square have. Combine this with the fact that Square Enix has recently pared down their business to be more focused on its core games, which further clears resources.
As for a timeframe; My prediction is that KH4 will be released sometime between Q3 2024-Q2 2025. I'm leaning toward Square Enix and Disney wanting the game to release worldwide by November 2024 to make their year-end results look as positive as possible.