Before anything else, I have to think those kind souls who create these kind of threads in Stark Mountain rather than Policy Review. Thanks a bunch people, at least here, some of the non-PR people who aren't absolute morons can comment. Of course, you do get the weirdo or two, but still.
The biggest problem with Pokemon specific bans is that you're altering cartridge mechanics in a way unlike other bans. For example, the tiers might be considered a violation of cartridge mechanics since they can't be enforced on wifi, but they are more of an honour code like the Sleep clause, and generally, more acceptable to everybody, since they ban a Pokemon in entirety, rather than a set(ignoring whiners obviously).
On the other hand, if we go ahead in banning specific things, it isn't likely to end very soon. At first, you'll ban stuff like Outrage on Mence, but soon, we will reach a metagame which is completely different from something achievable on the cartridges. Majority of the clauses are honour codes(and its no point arguing about them here), which were invented to attempt balancing a specific metagame. If we were to go for Pokemon-specific bans, we have to test these clauses(note: only related ones), since they may not be necessary any longer.
For example, hypothetically banning Spore on Breloom leads to a necessity to test Sleep Clause(council or otherwise, I'm not in a position to comment about that), which will take at least a month(basing off Jumpman's post). And when 5th gen comes out, we need to do a complete overhaul, retesting a lot of things. For example, say we got a 103 base Speed Ice-type with excelllent Defense and Special Attack Stat. We have to do a retest of Garchomp to see if it is not broken in the new metagame. It might even steeply drop to BL, just because it lost Outrage/SD/whatever you want to ban on it, when it might have been able to much better pre-specific ban(which will also have to checked by the council, prolonging things even further). I don't think we really want a metagame where things are nerfed to the point that they can be used, just for the sake of using them, since it is a honour code which seems worse than our clauses, which seem to actually serve a specific purpose.