Firstly, We only ban things because they are too powerful, or introduce too much luck. Uber Pokemon fall into the first case. OHKO and evasion clauses are a bit of both. If there were a hypothetical 500 base power move with no recoil learnt by many Pokemon, we would be justified in banning that.
We do not ban things based on luck, unless you would like to direct me towards a reference that indicates otherwise. We have OHKO and Evasion Clause because they were old customs, much like Sleep Clause, that at the time they were implemented in their respective metagames, weighed significantly more than they may do so now.
Rather, I think it is more appropriate to say that we ban things because they are too powerful, and reinforce the idea of a more competitive environment. Whether or not that includes luck as a factor, that is up for the community to decide, but it has never been a part of our suspect policy.
And for the record, they are now attempting to test Pokemon with OHKO and Evasion Clause absent.
Stealth Rock, while it has major impacts, introduces no luck and is in no way too powerful. Getting rid of it would change the metagame, but the official rules should not be changed solely to change the metagame If you want to play some matches without SR, by all means do so. Set up a server with a ladder where it's banned. But I don't see it becoming the official rules.
I'm tempted to argue how you're incorrect, and how SR is too powerful, but I'll refrain.
Anyway, if you truly believe the rules should not be changed solely to change the meta, then what do you believe the policy review is for? It is to help promote the most healthy, competitive Pokemon community possible, for Shoddy and Smogon. In order to reach a destination, we need change to happen.
Clearly the meta didn't collapse when Garchomp
was still here, but I'll think of a more appropriate example.
So far we have managed to allow Wob, Latias, Deoxy-S, and Manaphy for a short period, in to our main stream battles. Our battles have fluctuated, so has the way the game has been played, and even the tiers. I think the fact that 3/4 of those Pokemon are still in Ubers is a testament as to where they should be placed, or where they will wind up staying in the future. However, despite this, we have maintained a relatively healthy meta, even with the inclusion of these Pokemon. But if we were able to maintain a style of play in which the community thrived upon during these circumstances, then why follow along with the suspect tests at all? Why even bother?
It's to promote
change, to bend the rules and regulations and the way the game is played to our ideals. Smogon promotes to replicate the cartridge, but it does not decide how the game is played. We do, and for that sake,
the official rules are changed to change the metagame.
I think the prevalence of SR owes more to it being learnt by a lot of things than to the move itself. If more things learnt Spikes, we'd probably see a balance between usage of Spikes and of SR (and some teams using both) - they hit different things, so use what you need to hit.
13/30 of the top 30 OU Pokemon in the NOV 2009 statistics are immune to spikes, and for giggles sake, 21/30 are immune to Toxic Spikes, and 4/30 are able to switch out via Natural Cure.
No Pokemon used in OU, except for Clefable, are immune to Stealth Rock.
Spikes takes 3 turns to maximize its effects, in which event, the most amount of damage it can serve on switches is 25%. Toxic Spikes clearly is another matter in terms of damage, but it too takes 2 turns to maximize its effects. If a Rapid Spin user comes in to play, you either are forced to play your Ghost type to prevent the loss of your hazards, or you risk wasting 2-3 turns in your battle, in which you will need to use another 2-3 turns to gain back that advantage, and after you kill off RS user.
Stealth Rock takes a single turn to set up, which means that even if Rapid Spin is used, the turns equal out, and the playing field is reset in terms of turn advantage. To gain the advantage back, it again merely takes a single turn.
As from a damage perspective, Stealth Rock takes a single turn to do the equivalent damage that 3 layers of Spikes will do, and has the potential to double that damage, for the same price.
Toxic Spikes and Spikes do not heavily influence the entire metagame, and are not required to win within a high CRE on all teams without significant disadvantage.
Stealth Rock effects the entire metagame, in every tier,
heavily, and is of a severe disadvantage to the player that chooses to ignore using it themselves.
As far as team handling is concerned, one does not need to fear that SR will serve no use to the user, meanwhile it is not uncommon for a player to find out he wasted 2 turns with Toxic Spikes to find out his opponent is using all Steel Types and Levitators/Flying types. This applies less to Spikes clearly, but it still of a great concern when team building. This does not apply to Stealth Rock.
Toxic Spikes and Spikes require
team support in order to work.
Stealth Rock does not.
It is the most risk free, rewarding, stand alone move, influential piece of garbage I have ever seen. It reminds me of Pot of Greed/Graceful Charity from Yu-Gi-Oh.