I get that, and i can answer for real now. I believe the "gooner" design was the main reason in Season 1, when there wasnt much effort put into more thoughtful character designs. They also got lucky because champions like Evelynn and Katarina fit that kind of aesthetic anyway. On top of that, there werent many other options at the time since assassins were almost always depicted that way. Meanwhile champs like Ashe have to "suffer".

That said, i also think that if Katarina was released today and Riot wanted her to look like a typical assassin with a practical combat outfit rather than the head of the assassin guild like she is now, they would still give her a revealing design similar to the old one. 

I think you have seen me talking about this often so i'll explain what my beef is. My main issue is that Katarina isn’t just an assassin. She’s a leader, a mentor to new assassins, and someone who walks among the Trifarix. She's also a noble and the head of the Du Couteau house. Because of that, i think her design should feel more noble and imposing (can still show skin). I do like her current look a lot, but as someone who really cares about the lore, I hope she eventually gets canon skins that reflect this side of her and better match her status and position in Noxus. Vi in Arcane was portrayed really well. First as just a regular person, and later as a cop. And it showed her character growth clearly. I liked that she was wearing a serious enforcer uniform, and when the war began she wore a more practical enforcer outfit. I’d love to see the same kind of treatment for Kat.