So? Ground and Fighting also resist spikes and stealth rocks. That's what ruins fire types in general, they're so fragile, but on the other hand they're suppose to be pretty good offensively. Ground types especially are bulkier, especially on the physical end. And have an important immunity to electric. I guess that'd leave fighting at the end of the stick, but to be honest it didn't really need the fairy nerf at all. The only fighting types are considered actually overpowered usually have a second typing that cancels everything else.
I also don't see the problem with that. All that it would do is make it so that special Dragon types actually stand a chance since the physical ones don't really learn good physical f9re type moves at all, but destroy fairies with either steel or poison anyway. Which pretty much all of them have. No one ever complains that ground types kill off flying types anyway because they all have rock coverage, or water types easily killing off most grass types because so many have ice beam. Again, you can't just unnaturally make a pokemon under a certain type worse, because usually one of the reasons they're so great is coverage.
That seems a bit too unnatural though, I prefer adding fairy over that. I think the way that things usually are balanced out and should be balanced out is that each type has a niche, rather than making every type have the purpose. That's why poison is so useless too. It's intended to kill off pokemon slowly and annoyingly, but the problem is that way too many pokemon know toxic. Dragons were good even without even using dragon type moves.
