Although I have only read the first post (I’m not reading some 300 posts about pokemon, no thanks), I think this response is entirely justified.
Pokemon has been dying. Slowly, but it has been dying. With the release of DP, it received some brief treatment, which only masked the problem, like putting bandages over a lethal infection. This has only allowed the problem to fester and develop into something worse. Recently, with all these unbannings, or attempts at unbannings, it seems as if you're just trying to kill the game faster.
Near the end of adv, the game was definitely dying due to a lack of interest. This was of course expected. It was nearing the end of an era, and people had gotten bored with the current metagame, looking forward to the new one DP presented. Much new blood was brought into the picture with DP, and the game experienced a temporary rejuvenation.
In terms of player interest, the game is still going strong. But those same active players are killing the game. Gamefreak left us with a highly offensive game, something we haven't seen since the very start of the franchise in RBY. If we start allowing ubers into the standard game, all we're going to do is restrict our options further, rendering the game a shadow of its former self.
Even before all of this unbanning nonsense started it was almost impossible to cover all your weaks. Even the best stall teams couldn't stop everything, and often seemed to collapse to some big threat, regardless of what safeguards they included. Some of the most notable pokemon that caused this are ttar, chomp, and mence, none of which were ever even considered to be too powerful for the game, with the exception of before it was released, which doesn’t count. TTar and mence have the unpredictability factor going for them, while being able to cause massive damage even after your opponent knows their set, and if you guess wrong you could leave your team crippled to some other threat on their team. Chomp seems to have finally lived up to his hype, thanks to outrage abuse and the protection sand veil grants. And then we had mixape with only a couple true counters. Having a couple overpowered pokes is manageable - people can get around it. For example, ttar was arguably the best poke in adv, but wasn't banned; since there were only a couple pokes that posed a huge threat, people could stack counters against them and be prepared, but now that's not necessarily the case, as half of the pokes in OU are capable of destroying teams with minimal support. The problem is we carried over the adv mindset to DP, that most base 600 pokes were not too powerful for the game, and that non-legendary pokemon, however stupid it sounds, are not uber under any circumstances (unless we’re talking about wobbuffet, who we decided was still uber after finding it uber in adv… sound familiar?). As a result, we ended up with multiple beasts in the game, which people have just accepted as being there, a part of the game, even though they unbalance it.
In other words, the game was already breaking at the seams. A very thin thread was holding everything together, and that thread was getting continually worn down. Well, guess what? It's finally breaking. Ever since the shoddy test phase of deoxys-E, that thread has been stressing like it never has been. The physical inclusion of deoxys-E into the metagame was not what broke it, but just look at what is happening now. It has paved the way for the acceptance of many new pokemon, previously considered uber, into the OU metagame. This will not make the game somehow "better." It will only make finding balance in teams harder, and turn the game into something of the effect of rock-paper-scissors, matches getting determined before the game even starts, due to team choice. Either that, or we're essentially going to be playing ubers-lite. Neither of these two scenarios is particularly desirable.
Ladies and gentlemen, our mistake was not in banning these pokemon from the start. Our mistake was not banning enough. I think that the only way we are truly going to obtain a balanced game, one with the highest number of viable pokemon and strategies, is to take our old tier list… and start removing the biggest threats in the game from it. We would slowly remove threats, and when we finally found a balance of pokemon, we would use that. If a certain wall became too prominent (ie. cress), we would remove it. If it left a certain sweeper too prominent after that, what do we do? Remove it for a while, as well. Then compare the level of balance between the two games we had created – the one with both the wall and the sweeper, and the one without. We just keep repeating this process until a selection is made that seems balanced. You seem to want to balance the game by adding more to it. This is only going to make the game more and more offensive. I think we should strive to make both offensive and defensive play viable.