The only confirmed thing is it's super effective to dragon and I doubt they want to make it a 'better normal type that hits 3 types for SE damage' that would completely ruin the niche of Normal type. So here's batting it has a normal range of weanesses and resistances with no stupid immunity business.
Quite frankly, it only doesn't sit well with you because you're a misogynist (evidenced by your rection to something girly having a possible iota of toughness, and your completely inappropriate use of the word (BAN ME PLEASE).). Believe it or not, fairies, as a whole, aren't just the standard disney tinkerbell stuff you see.
In many legends and origin, they're like a metaphysical spirit, like angels and the like (and before you start calling angels badass, the bible has some angels that engage in fist fights from night until dawn. They completely slaughter evil spirits and dragons, biblically, and are more like protectors). And, even though today we imagined little pure four year olds with blonde, possibly curly, hair, originally they were tall beings or wise trolls. Some, fairies, on the other hand, are described with a malicious nature. They also kidnap humans and lead them astray before torturing them with their mythical powers.
Keep in mind, fairies are also noted to be nymphs or tree spirits. In a Japan, where the religion Shinto is one of the more widely practiced religions (and a great source of inspiration for the franchise), such "fairies" or elemental spirits suddenly make sense, especially with their supereffectiveness against other mythical creatures. Dragons, in the franchise, are noted for their large, destructive attacks and nymphs and spirits are noted for their more protective qualities of their domain. If these types were called nymphs, spirits, protectors, angels, guardian type or whatever, you probably wouldn't be as incensed as you are now. But the god damn word "fairy" inspires some sort of asspained brutality because it implies something feminine can slay a dragon. Well, fairies aren't just mild mannered little girls with butterfly wings and, even if they are, the fact that you're so incomprehensibly angry over this just denotes the person you are - especially since you go on homophobic tirades to just to justify your point.
From a gaming perspective, and from a type perspective (especially as we learn what other strengths and weaknesses they have) it makes sense. Now take a seat because no one should be here for your chagrined womanhating ignorance.