The problem with KH3 is people naive enough to expect good storytelling in a Disney anime game.
I mean, it definitely can be done. It's not like Nomura is a terrible writer. At least, not in my humble opinion. But it's like what other people have said here before, he needs a co-writer, and there's absolutely no shame in having one. Nomura's the idea guy, why not have Tai Yasue help him out with cleaning things up and making the plot smoother and easier to understand? He's been in the franchise long enough, I'm sure he's got a strong enough idea of what the series represents.
I don't think it's the ideas that people have an issue with, it's the execution in how it's done. DDD had the whole Time Travel plot point added in, but required a bunch of rules that confused a ton of people. I honestly feel like if DDD didn't have time travel as a big plot point, or maybe reworked it so it's not as convoluted... Or even introduce the Worldline concept in DDD itself, a lot of issues wouldn't be there. In fact, a lot of the issues I'm hearing now started from DDD.
People had issues with 0.2, but only because we thought that we were going to save Aqua there, and because people felt Mickey just abandoned her (even though Yen Sid tells Riku right then and there that if anyone had said anything, Riku or Sora (DEFINITELY Sora) would stage a reckless attempt at a rescue... And not to mention that Mickey himself didn't know how he was gonna leave at the time).
The only other time people really had issues with the series other than DDD is Union X, because that's way too much lore for a game that's pay-to-win and isn't all that rewarding. Now, if we got a console remake in the vein of FFXIV, that'd be a dream come true... But since we're visiting Disney worlds, that's probably a lot of legal licensing headaches that might not be what Square wants to deal with right now, seeing as how they're working on the DLC and the next title (among FF7R and any other potential titles they've got over there). So an excellent story can be done, it just needs proper polishing and extra focus on certain things.