" Young kids love legendary Pokemon becuase they are cool and really powerful (a.k.a. easy). In fact, this is why the World Tournement is allowing Legendaries. It is becuase most of their users are now younger kids (worse then with R/B) and they know damn well of that. "
It is mostly an implication, but its there. Most importantly almost all the legendaries are banned from the world tournament either directly or indirectly via the level cap.
For the most part legendaries are not broken though. Uber tier being dominated by legendaries != legendaries are mostly broken. There are 23 banned pokemon including 2 forms of Giratina, and 4 forms of Deoxys. Removing the formes (save Sky Forme Shaymin) and non legendaries you have 16 banned legendaries. There are ~35 legendaries in game. I say again, most legendaries are not broken.







