Lets talk keeping and changing Character Identity

So lets cut straight to the chase here, when is it OK to change an identity and when is it not Riot? if we look at the past reworks and posts you mention identity in multiple ways

People asked for Lee sin and Kassadin changes and you respond with wanting to keep their Identity, but then you rework Cass and Sona changing their Identity OR you deliberately rework the champions Identity (Soraka) I understand some champions NEED an identity change because they are just a complete mess ( ) but there's some champions which had ether a very unfun, warping gamestyle brought on by their identity, Before all the nerfs NOBODY liked to face Kassadin because of his rift walk and Lee being able to do everything warped the entire jungle and even some jungle champions, and yet you use the "Keeping the identity" excuse but then proceed to change the identity of champions that weren't needed (Soraka, Sona, Karma, Cassiopeia) honestly it brings up a question in my mind, does Riot not change the identity of some problematic champions because they can do flashy plays or is there some other reasons why some champions don't get identity changes even if their current identity is warping the game?

I'd like a Red to answer but I'm going to put my own personal thought about it, I think its partial Bias to the champions, Riot will be more hesitant to change a champions Identity if they like said champion, ether due to how they look, how they play or otherwise and it honestly makes alot of sense if you look at it, they refuse to rework Lee sin claiming its about his Identity then change Soraka from the ultimate of sustains to the strongest healer or how they say they won't Nerf Kassadins rift walk because its his identity but then they rework Cass to make what her Identity is, DPS poison damage, useless.

I know people will say the typical "but muh esports, but muh playz" in response to why they don't rework some champions identity and happily do so for others but to me its more personal bias, if the personal bias is BECAUSE of Esports and Plays then fine but as I said I believe it stems from people at Riot being somewhat Bias of certain champions (I mean we'll never see a Teemo rework for example. Phreak would blow up the entire HQ if they did, or in translation Teemo will never be reworked or have an identity change because people at riot like Teemo, personal Bias)

again as I said It be nice to see a red post their stance on the issue but of course others are free to post as well.