XY is a complicated set of games, and it's unfortunate that the discussion about them typically boils down to 'they were bad'. It has some of the most significant leaps in the series, like the online interface, vastly improved training mechanics, or Pokemon coming to life through Amie with some incredible 3D modeling and animations.
It even has a-lot more to do than most of the 'first pair' games, like RS, DP or BW. There's more opportunities to play in Triple and Rotation Battles (Battle Maison, Le Wow, etc). Berry farming was put back in the games after BW removed it entirely. Battle Chateau had daily battles against the CPU for exp. and money. Friend Safari made finding Hidden Abilities or Perfect IVs an absolute breeze compared to BW, or even SM. You could finally customizing your character, and make videos for them with the PR Studio. Super Training had an extra run of soccer games to play for fully EV'd 'mons, just for the sake of adding more to do with it.
With such a strong foundation of features and innovations to work with, Z, sequels, or some kind of similar update might have been redeemed Gen 6 in the same way that Platinum or BW2 did for their respective generations...Unfortunately Kalos was terribly under-developed, and under-supported, leading to its reception as a mediocre entry. Story and characters were painfully shallow, even for Pokemon game. Parts of the world feel unfinished, like the locked doors of the Power Plant, the train station to nowhere, or Anistar Sundial. Then in 2014, Mega Evolutions were retconned into Hoenn, and Gen 6 suddenly revolved around ORAS after only a year. Mythicals had their special events in ORAS (Unbound Hoopa and M. Diancie), and you wanted to do anything with Zygarde, you had to buy Sun and Moon. Kind of infuriating when you realize that SM wasn't a complete game either, and got its own 3rd Version in Ultra Changes a year later.
In the end, XY was a beautiful, tragic mess of a game. RIP...
