When we see gameplay footage featuring a fairy type, I'd just want to remind all to pay attention to any changes. It wouldn't surprise me to see a fairy nerf given just how strong the type is (honestly imagine Psychic but stronger defensively) and they nerfed steel and I wouldn't be surprised if fairy gets resisted by more types since Hyper Voice is really damn spammable in VGC. (At least I think it is.)
I don't think Fairies are strong enough yet to warrant a nerf. Just like Dragon wasn't a problem until Gen IV or so, when we finally had got enough of them to build entire teams around, and they had the moves they needed to utilize their STAB. Fairies are currently held back by a relative lack of moves, and that the Fairy Pokémon themselves aren't really much to cheer for. Just like the Ice type, which on paper is an amazing offensive type, but whose Pokémon are overwhelmingly defensive. The qualities of the Fairy type is currently like those of the Ice type: Tons of potential in theory, but not yet realized because the 'mons and the moves are so lacking.
The existence of the ability Pixilate might skew the stats a little, since that allows Sylveon, Mega Altaria and Mega Gardevoir - the most prominent Fairy-type special attackers - to abuse
Normal moves as pseudo-STAB. Fairy types without Pixilate sorely lack tools to be as frightening as those three, so unless Game Freak keeps spamming the ability, I think we'll be fine in the future. Likewise, the Fairy physical attackers - Azumarill and Mega Mawile - gain most of their offensive presence from their abilities, rather than qualities unique to the Fairy typing. Had there only been two good physical Electric attackers, and both of them had Huge Power, I think people would have called the Electric type overpowered. On the defensive side, Clefable and Mega Diancie are also blessed with some of the best abilities in the game. No wonder why they do so well.
TL;DR - the Fairy type as we know it today gets most of its perceived strength from a few prominent Pokémon with gosh-darn strong abilities, rather than qualities inherent in the Fairy type itself. There aren't many good Fairy-type moves, and most Fairy Pokémon have underwhelming stats. If anything they're saved by their
defensive qualities, and augmented further by good abilities.