Not a fan of DLC and also of they not really finishing the trilogy

And you're incorrect.

I don't know what you want dude. You define spinoff one way, I define it another. You've yet to provide what your definition is, beyond something about it meaning irrelevant and ignorable. DDD still isn't the main story, I'm sorry dude. It has details that matter, but it's a spinoff. Spinoff doesn't mean irrelevant, not in my book. I explained it further in the post you responded to, but you obviously don't want to read that.

It doesn't fit spin-off even by your own definition. Unless you're willing to about the only difference between a main title and a spin-off in your eyes is if it features a sequential number in the title.

I've never said it was just the number, dude.

Then nothing else matches. Titles like DDD not only feature immensely important chapters of the story, but have gameplay mechanics that are featured in subsequent games. 

Yeah but it isn't the main story. Important, sure, but not really the main quest.

Kingdom Hearts is a different beast because of how the non numbered games stradle line. A spinoff is a new product based of an existing work. A spin off is self contained product that expands on existing elements (plotpoint, characters) while not altering the main series; meaning it should it have no direct consequences if skiped. Kingdom Hearts completely shits on that not just from a narrative perspective, a gameplay perspective as gameplay elements from these non numbered games make it back into mainline titles. So its not fair to call them spinoffs because how important they are to series from story and gameplay angle. I think interquels is a much more appropriate term.

But the idea that it took 13 years for the next main installment is a sentiment I agree with. I wil not count non numbered titles.

Okay, cool, thanks for proving that you haven't even played the games (or at very least haven't played them enough to know what the story is).

Dream Drop Distance is literally the next sequence of events after KH2 for Sora and Riku in which they progress the main plot forward. It's where Xehanort makes his next move following KH2. The idea that DDD isn't part of the main quest does more to show how unprepared you are to even have this conversation than to prove the point you're trying to make.