Im just gonna go ahead and say it.

Ezreal can beat her.

http://www.auplod.com/u/pdolua802d6.png

like the only top lane that can almost make a difference

Play literally anyone with multihits or combos involving tons of hits and her soul pull is suddenly useless. (hitting her when ur soul is pulled reduces the duration it exists by 1 second per hit)

Examples of people capable of this:

With Darius specifically, you can just all in her when she pulls your soul and she can't do anything about it. In fact, the cast animation is so long that you have tons of time to just walk up to her. Once your soul has returned her damage output drops significantly.

Let me guess. You're the type of who prefers to stay inside Illaoi's ult instead of walking out of it.