Why does illoi even exist in game ?

So i recently started unranked to diamond on new accont, i want to learn toplane and speciale i want to learn fiora, I know between my self that toplane is shity and useless role but i want to give it shoot. If all cancers and bullshitt in this lane There's 1 champ i cant stand facing her and she leggit unbaitable and not counter play. Its illoi ... Wtf is this bullshitt champ ? Even when i play on my main in diamond, illoi is bullshitt but at least dont have to lane against her. She simply no counter, Her only realisitic counter play is rng and i mean by that, Ur team win other side of map and carry u, Even jgl pressure is uselss against her. She's by far most aidss thing in this game. What trigger me most, she can miss her E and still out trade, Hell she can even 100 to u with r spam w. She's impossible to deal with, She does insane amount of dmg, Her healing and sustain is just bullshitt, She has stupid high base tank stat, Her w range and her q hitbox makes her impossible to deal with from mele and like i said, U can sidesetup her E and clear her passive, She will still out trade u and if she manage to her E on u, You are bascly out of lane bc ur health bar is 20% i played this game for 2 years now, I been throw all bullshitt champ nerf and buff But seriously illoi is just bullshitt and need to be removed from game pending rework and riot should fire her designer for creating such toxic caratere that her only job is to make u rage quit with out needing brain and being good at this game.