This is a really excellent summation of how I feel, and why KH3 really hasn't connected with me. It seems to have lost track of its mandate to play against type and now it's just another functioning arm of the Disney media apparatus. Nothing about the way this game is being delivered really seems to separate it from any other bloated meggga franchise the Mouse House exploits for hype points, and while there's certainly nothing wrong with the popularity it has garnered in and of itself, I really wish it could have maintained that flavor of unpredictability (not as a narrative crux) and archetypal self-awareness. The aesthetic and emotional iconography of KH is always what has defined it for me, and KH3 seems to have overreached in its chase of a specific 21st century brand of "updated" commercialism that is just the antithesis of what I would have wanted for it.
With that in mind, I think I'm likely to follow future developments, but I probably won't go out of my way to play the games. I'm not interested in buying any more game consoles/systems anyway, so while I know that my curiosity will drive me to look in on the series and watch cutscenes and engage in the community, I wouldn't say I have any intent of being strictly invested. I'd say that KH3 is the last game that gets my heart.
This is exactly how I feel, but put in a more eloquent way, as you usually write. KH3 feels more determined to garner new fans as much as possible, with the method being having it as "mainstream" as it possibly can, with no room for anything offbeat or unconventional that brought charm to this series in the first place. Although, I wonder if this is only what they are pushing for in the marketing of it; that KH3 might bring in some abstract creative flavor, in certain segments at least, that the marketing team just decided it wasn't worth showing off in favor of fancy graphics and worlds everybody already expected.
As much as many people disliked DDD, to me it really did make me love the series and get excited for KH3 all over again. It was honestly very reminiscent of KH1, with the original ideas of the Sleeping worlds (that for once was an element that didn't feel forced and convoluted) and the settings of worlds that nobody expected but were very charming and beautiful (worlds like the nostalgic Traverse Town but expanded and the unparalleled world of Fantasia). Even with the time travel, which as you mentioned was only a plot device Nomura used as a crux to force in some inorganic "plot twist", the rest of the story and game still holds up the creative spirit of KH1 imo, and had fitting arcs for the two leads we've been with since the beginning.
It honestly feels like DDD was actually the KH3 we waited for, and this is KH4.
It depends on a lot of things really. If Sora and Riku continue to be the protagonists post-KH3, whether or not I'll have to buy yet another game system to play the next game, what Disney movies they decide to use for the game (KH3 already features mostly films I don't care about), etc. But, most likely, yes.
Yes this is me to a tee. Honestly, Riku is the only character I care about and feel invested for at this point, being the only one with a compelling and fully realized yet still growing character development. I honestly expect Sora won't ever be anything but a generic anime audience surrogate (based off of what we've seen of him the trailers so far), but hopefully KH3 will prove me dead wrong. As for everybody else, I just don't have that much attachment to them except for the potential of what they could have been and just the "idea" of them being characters I'd care for (although Axel's character and hinted arc in KH3 is starting to look a bit interesting). Enough for me to possibly watch cutscenes of future games they might be in, but not enough to justify buying actual games for anymore.
Final note: it might be possible after KH3 this series might feel more bold in it's themes and world choices, maybe taking a more casual and freeing approach on what it wants to be; but no one knows what direction the next saga will take after this.