Why the nerf exactly? I hear conflicting answers from r/ireliamains and from others. "Its because her pro play is too strong" and "They want to fully gut Irelia mid" So I am asking because I don't know. Why is it so bad for Irelia to go mid?
Because she's far too good in mid. There isn't a single midlaner in pro play who can win lane vs Irelia, and most games Irelia gets lots of solo kills on them. She's just far too strong in the right hands, which means that she can't ever be allowed to be viable in solo queue... RIP.
Good , nerf her more please
Unfortunately not nerfed enough. ONly for midlane because midlaners are crying everytime a non mage dares to enter the lane. So they nerf mid irelia so that toplane irelia can win against everyone.
Just irelia on midlane can kill u whenever she hits R on u, with E hitted it's just an overkill even under tower. She can chase u from lvl 2, and almost kill u whenver she lands stun with her passive. She is even still good on top in a good hands.
with new passive is just too good on her vs mages, giving sustain mr and dmg. On midlane in my opinion she gonna loose vs good 
because he can block her stun and r with windwall, which is not hard to block, irelias R is coming from behind, so yas can just press W behind her and it will block R. 
may give her trouble because they may play totally def under tower, ryze can go aftershock, has snare and azir is mobile and can just r her back into tower, while vlad uses pool and have sustain. 
with 2 dashes on lvl 6 can outplay her.
She needs to be nerfed more.
riot has a fetish for nerfing irelia
I don't know what I expected when I asked this on the forums. [zombie-nunu-bummed]
