Wanna know how to shill for a new type in the very first generation it got introduced in?It’s simple, really.

>Switch the typing for a lot of Pokémon to it, usually from Normal.
>Slap it onto previous monotypes, solely on the basis of them being cute or pink.
>have the new typing supereffective against three of the most common and popular non-starter typing in competitive, even completely immune to THE most popular one
>pair it with another type that’s capable of STAB supereffective attacks against its ridiculous minuscule number of weakness. or one of them, at least.
>have the teams of story characters, even the most important ones, share the exact same weakness, and to the new shilled type nonetheless.
>also, give the new typing a random resistance (such as x0.5 Bug) to cover for the weakness of the secondary type it’s paired with
>smartly advertise and present the new type in such a way that the typing is overwhelmingly admired rather than criticized for being broken

And that’s how you keep the newest type’s ridiculous strength and low number of weaknesses for at least two more generations, perhaps more.

I don’t even mind Fairy Pokémon. Some of ‘em are cute, and decent in battle, but they seriously feel like a crutch type.