I know that Game Freak puts effort into every game, I just think the progress and effort is most obvious in XY. Dismissing this based on the comparison of sprite development to the 3D development does not make sense to me and it is not a comparison I made in my post. I do not know if BWB2W2 could have been made on the 3DS, but it is my opinion that they should have held out on the new generation until thy could create the games for the 3DS. GameFreak thought that the Gen V product was complete enough to release and so it happened. Many of the sprites in Gen V were just recycled from Gen IV. GameFreak will continue to develop how they see fit, but that does not mean fans have to like everything they do. Of course Pokémon will always have its limits. Even with its limits, Pokémon outshines many other games and will always be a worthwhile experience for me, but that's not to say that it will be for you.
Unfortunately you've not made any clear comparison with regards to effort. What you've mentioned earlier was this:
"Progression is inevitable" is not a valid dismissal of Gen VI, Gen V (or a good part of it) existed at the same time as the 3DS, but did not take advantage of the new system. A lot of the development of the game had to be put into developing models for people, Pokémon, buildings and landscapes. Just because a change was inevitable doesn't mean that we should take it for granted.
Which I take it to mean:
1. Assuming that Gen V 'did not take advantage of the new system', and should have.
2. Placing emphasis on model development for various elements of the game.
For point 1, no one has an answer to it. It could've been that Game Freak could have planned BW/B2W2 for the 3DS but chose not to do so. Or it could have been that they decided to push ahead with developing it for a more familiar console in order to make time for the next generation games on the new console.
For point 2, seeing as your only comment about efforts was with regards to model development, it makes sense for me to use sprite development as a comparison. In fact, you've dismissed BW/B2W2's effort in this regard when you assumed that they've reused the sprites from DPPt. DPPt, or rather Platinum, had only partially animated Pokemon sprites (animated only upon entrance, with fewer frames), and back sprites were the 'partial view style' used since the first generation. Whereas BW/B2W2 had completely animated, full frontal and back sprites.
In a way, you're right in that the 'efforts', or what I call changes, in XY were very obvious seeing as we moved from a sprite-based graphics to 3D models with changing camera views. But I'm not sure if such changes have blinded your judgement in a way that could've made you over-credit XY while undercrediting BW/B2W2 in terms of 'effort'.
That's true. By the way, before mega evolutions and fairy types, there were dragons all over the place. If it wasn't a dragon, it was a pseudo legendary or a few overused pokemons like Blissey or Starmie. So the battle diversity wasn't that strong either.
I find that there's a general limit as to how diverse the pool of powerhouse Pokemon can be in any tier from OU to NU. Usually about 40 Pokemon would have a usage rate of more than 5%, of which roughly 15 Pokemon would take up double-digit usage rates. So if it wasn't dragons all over the place, it'll just be 'something else'. And right now I believe it's pretty obvious which are the regulars taking that top 40 spots this generation. Ghost swords, firebirds, ninjafrogs and the two brozards anyone?
Even if Game Freak churns out more mega, this isn't going to change what seems like a statistical trend in the competitive scene.