I've always been very skeptical about this happening, but admittedly Disney+ made it more likely than in the past. That said, as has been mentioned in the Disney+ thread, Disney seems to be focusing less on their streaming platform considering it's not really paying off well long-term as much as they'd hoped. I feel like if a TV series to this was greenlit, it might be one of the ones put down if they start to put out less streaming content.
TBH, as a KH fan, I never really wanted this anyway. I know they'd simply re-tell the first game over again and I think the game series itself has re-told that story so many times already.
And I have a feeling a remake of the first game may end up happening over the next decade for PS5 or PS6, too. But still I would've watched it if they brought Osment and Gallagher back for it.