Alright, I've been intending to steer clear of this thread for a long time due to how immensely low quality it is, but whatever. Wall of text, commence.
At first I was pretty opposed to a ban, a lot of the reason being that Swagger, in theory, does not completely take control away from the opponent. For example, we have Moody, OHKO moves, and Evasion banned. But why aren't accuracy lowering moves banned? The reason is simple: the added luck factor can be easily negated by switching out. While Moody could leave you helpless against Substitute/Protect spam, nothing can be done against Evasion except phaze, and OHKO moves are just plain dumb, accuracy lowering isn't nearly as threatening due to the fact that players can effortlessly fight against it.
Initially, Swagger appears to be in the same situation, as confusion is also negated by switching. However, this isn't quite as much the case in practice. The opponent has absolutely nothing to lose by hitting the switch-in with Swagger again, recreating the 50/50. In addition, whether the free turn generated by the switch was taken advantage of with a Thunder Wave, Substitute, or Foul Play, the Swagger user is able to maintain his advantage of a 50% free turn chance, or even improve it if they manage to set up a substitute.
I didn't think that this was really much of a big problem, as I felt that the Swagger user wasn't necessarily playing to an overall advantage here. I've faced it on the ladder a couple of times, and when I lost, I never really felt like I was robbed by a cheap strategy. Rather, it was more like losing due to an untimely Hydro Pump miss or something, more along the lines of "If full confusion didn't activate for ONE extra turn, I would have won. Oh well." Essentially, the hax doesn't seem any more likely to fall upon the player going against Swagger than the one using it. For example, if a strong Substitute user manages to get a couple of free turns, that could be the end.
It was the definition of "uncompetitive" posted earlier that made me change my mind about this. Contrary to what I initially believed, Prankster Swagger does in fact remove control over the match from the victim it is used against, despite the fact that switching out removes the confusion status. Outside of getting excessively lucky with 50% hit chances or running gimmicks like Contrary Shuckle with Rest, one player will be following the Swagger/Thunder Wave/Substitute/Foul Play formula, while the other will be blindly hoping that their Pokémon will get a free turn to get off a hit. This fits the "uncompetitive" definition perfectly.
I'm actually only neutral to a ban now, I still believe that there are some favorable arguments against a ban. But I'd rather not list them, since it'll only spark arguments about things that I don't really care to argue about. Rather, I want to talk about why a full ban on Swagger is thoroughly unecessary. I'm going to start by going through the different things that support Swagger and how they affect it (I don't know why there are some that want Swagger/Foul Play combination banned, come on people that makes no sense).
How would the strategy work without Thunder Wave?
Essentially, no different. Thunder Wave has the great ability to lower move chances from 1/2 to 3/8, while also letting the Prankster user hit first with Foul Play. It's also permanent, adding extra punishment to the opponent for switching. However, without Thunder Wave on the set, opponents don't really have any more options than they normally would. It's still a matter of "switch out and take another Swagger or stay in and hope to actually hit the opponent". While the odds of winning with Swagger would be somewhat lower, the strategy is no less uncompetitive without Thunder Wave.
How would the strategy work without Foul Play?
Foul Play is an important part of the set, allowing Swagger users to hit their opponents for massive damage thanks to a boosted Attack stat. But like Thunder Wave, it's not so essential that removing it will alter the uncompetitiveness of the strategy. If Klefki needs to run Draining Kiss over Foul Play, it'll certainly be hitting for a lot less damage on its free turns. But this doesn't give the opponent any more ability to fight the strategy. They still have to deal with immobility for 5 out of 8 turns, chip damage from hitting themselves in confusion, and the opponent hiding behind a Substitute. Foul Play is not essential to the strategy.
How would the strategy work without Substitute?
This is where things get a little more interesting. Substitute is one of the things that makes Swagger so effective at what it does. While a 3/8 chance to move isn't great, you certainly don't want to give something like a Garchomp a single chance to get lucky and start slamming things with Earthquake. Substitute is how the free turns generated can be spent, allowing Swagger users to dodge otherwise deadly attacks when the dice don't roll in their favor. However, Substitute is VERY obviously not the core of the problem here, having near-infinite uses outside of this stupid gimmick. I don't think I need to convince anyone that any potential ban involving Substitute would be a terrible idea.
How would the strategy work without Prankster?
Simply put, it wouldn't work at all. The opponent can now freely switch out to just about ANYTHING that can outspeed and KO the Prankster. Sure, they can just use Thunder Wave on the switch-in, or set up a Substitute, but that doesn't mean much. Spreading paralysis is an absolutely legitimate strategy, and such a set would simply use Swagger as a way of attempting to pseudo-phaze.
One argument I absolutely hate seeing is "Swagger has no use in the metagame, no harm in banning it. It's better than a complex ban anyways." This is flawed for two reasons:
-Swagger without Prankster does NOT fit the definition of "uncompetitive", as it doesn't force players into an uncontrollable situation. Rather, as demonstrated before, there is nothing that keeps the opponent from being able to fight back. Swagger alone boasts the same amount of uncompetitiveness as accuracy-lowering moves, or 60% flinch spammers. Fighting back is possible, through either switching, or using a bulky Air Slash/Iron Head resist.
-Bans should only take place when absolutely necessary. Banning Swagger alone is absolutely unecessary. In this case, a complex ban has the advantages of removing the source of the problem without taking away what is, believe it or not, a somewhat viable move capable of pseudo-phazing and buying free turns. As gimmicky as the Ditto strategy is, it's still viable as well. If Swagger isn't inherently uncompetitive, then there's no reason at all to ban it.
Overall stance: Either ban Prankster Swagger, or don't ban anything (I didn't argue that in this post, but it's still half of my opinion and I'd be fine with either). Banning Swagger alone is a terrible idea, learn to live with hax already.