imagine not nerfing anything in the game when irelia, jax, kaisa and urgot exist

Jax needs toning down, that's true, can't say much about Urgot, as I for one haven't saw any so far.

As for Kai'sa and Irelia....well, fun fact, they are considered by many challengers to be B tier, at best A tier, but nowhere near "overpowered".

For an example, guys at Mobalitics, who have Moriarty and a few others, have Kai'sa ranked as B tier for solo que, and A tier for high elo, while Irelia is A tier in mid, but B tier in top.

The problem with champions like these two cute ladies is that many players just don't know how to shut them down, nor how to end games, which is the most important thing. Kai'sa is similar to Vayne, a ticking time bomb, you can set her behind, kill her, camp her, what ever, but if you keep the game going for too long, you can't stop her anymore, and Irelia is also a very good late game champion. So I don't know, close, as in, win the game maybe?