Do you guys think they should have made a in-game explanation

No, because it's not necessary and probably wouldn't make sense.

>literally called the fairy pokemon

Bad example OP.

Better retconning shit is the existence of certain babies. Particularly things like munchlax.

>>29611776
No because then we would get more idiots that think ORAS comes after XY because fairy type is in it.

>>29611776
No. The fact that GF is so obsessed with "muh consistency" (see: Nidoran beig two different Pokémon, all of the retarded cross-gen evo methods, etc.) has been a detriment to the series as a whole.

It's not necessary because you can just assume that people realized that some previously known Pokemon had properties of the Fairy type that weren't noticed before.

>>29611776
Hasn't it been confirmed that there are different timelines?

>>29611924
Yeah, it has been. That was the point of the whole AZ thing, and the delta episode makes explicit reference to this alternative universe where they may not have mega evolution.

Oddly though... That's not what gf uses as the explanation for fairies in game. If you visit that village with the fairy type gym leader, a npc makes it pretty clear that fairy types were just recently discovered and that it's shaking up all the typings. Which makes no sense when you have this perfect alt timeline explanation right in front of you, but whatever gf.

>>29611924
no

>trying to make sense of pokemon
people say they discovered pokemon, then later on charactters that are 50 years old claim to have these pokemon since they were kids
pokemon doesn't make any sense

>>29611843
This. Hopefully with things like Fairy type in Gen VI, GF will be willing to retcon more dumb shit.

Especially incense breeding. Like why bother adding pre evos if you need very specific methods to get them

>>29611776
>have no qualms about completely retconning types, abilities, evolutions, and moves
>base stats? Unthinkable!

>>29611973
Perhaps something in the air (or just biological evolution reasons) has triggered certain Pokémon to adapt, giving them Fairy typing.

>>29613294
Didn't certain mons like Butterfree have their base states tweaked in gen 6?

>>29611776
>Do you guys think they should have made a in-game explanation to why so many mons had their types changed to fairy
They stated in XY that Fairy type is just a classification they made, in universe they are have always been the same, but they just realized they were a new type to some mons, and older ones they had also have it, so they were classified with it.