Birth by Sleep was awesome, one of the best ARPG's of all time, up there with all time favorites like Secret of Mana (if you ignore the multiplayer elements).
The article posted in the OP was clearly written from a "I played KH1, sorta played KH2, screwed around with the DS one and found it sucked (because it did), and looked at promo material for BBS and didn't play it" perspective.
Hell, it even mis-counts the number of titles in the series.
It's just a comment-fisher for ad revenue, or even worse, a poorly written article by a "gaming journalist" who bases his reviews off other reviews he read.
Seriously, KH1 was interesting but jumbled. KH2 was a stellar game with a bunch of the worst elements ever in an RPG, so it's hard to say if it's good or not. CoM was strikingly odd, seemed like they wanted to make a game with that battle system and decided to use the KH name to get sales. 358/2 was possibly the most boring video game I've ever played.
However, BBS was amazing. The combat was tight and varied, very little "button spam." You had 3 choices of playstyle to either choose from or replay several times and still keep it fresh. Instead of generic "you gain some levels" garbage like the other games, your playstyle influenced the advancement of your character through powering up your spells and making them able to be combined into all-new abilities that were often much more than "That spell from before, with 15% extra damage." There was even a "i'm on the bus and only have 10 minutes to play today" Monopoly style game, that in addition to being a nice way to waste a bus-ride to work, actually got you new abilities and powered up existing ones.
BBS was an amazing game. The best thing about DDD is that it seems to be following in the footsteps of BBS.
I haven't even mentioned the story in BBS, which while convoluted, was fairly coherent for a post FFVII Square-Enix game (yes, I said it, deal with it). At least it didn't beat me in the face with unnecessary cutscenes replaying stories from movies I watched 20 years ago. I think that's a good start.
If DDD manages to move forward in the vein of BBS while improving on it, it will be an excellent game. That's that.
Also, people don't seem to know what a "spinoff" is. CoM and 358/2 were blatant spinoffs. BBS was KH3 as advertised by the hidden FMV unlockable in KH2. Yeah, it's odd that it's called "Kingdom Hearts: Birth By Sleep" instead of "Kingdom Hearts 3", but haven't we all realized that SE is staffed by primarily lunatics at this point? I mean, what is a "Dissidia?" and then "Why duodecim instead of 12?" also all the extreme weirdness of the names of FFXI expansions, and even "The World Ends With You", which while vaguely catchy, had basically zero to do with anything. They could have named it "Melancholy Overcoming Despair" and it would have made just as much sense.
I don't feel like blaming the game for the fact that the SE guys bought an english thesaurus and went nuts. BBS was a main series title with a weird name. It fully wrapped up missing plot points from KH1&2. It was teased as the sequel to KH2 at the end of said game. Just translate "Birth By Sleep" from SE crazy-talk to english numbers as "3".