primarily the Zeds and Yasuos. The fact that this item becomes a MUST BUY in these match ups (and these fucking match ups seem to be every game considering Zed and Yas are pick or ban) limits builds, counterplay and creativity on all fronts.
You will literally know how it's gonna play out every game. My job is to rush Zhonya against a Zed, he'll ulti, I'll proc active, I'll have 1/4 health left and I'd have no choice but to either recall or stay in lane and get killed by his next combination...same BS every game.
And, honestly, Zhonya is an item isn't that great outside of its passive, considering they can shred through the fucking armor you build like its nothing.
Solution: give us more defensive itemization against assassins FFS. Real itemization where the opposing doesn't fucking know exactly what you're going to build against him every. single. time.