It is all because of how he is made, he is basically a non-unique champion aside from the passive and the bushes ability.
Regardless though I think the latest champions are not unique in any way. They are slightly different but they do things seen in other champions too. The mechanics are basically seen all over the champion roster. For example the new champion Kayn has the Yasuo E+Q combo in one ability but slightly less strong.
To be honest the reworks are way more unique than the new champion releases lately (See Urgot and Kayn for example) Kled was interesting, Ivern was kinda different but not much if you think about it he is a jungler support with only one real ability to help in ganks that is a skillshot and the rest of the kit being helping the allied laner. Bard is kinda the same but better at the moment, he can roam so essentially he is also a jungler/roamer who can travel the map very fast, he has damage and CC slightly more reliable than Ivern due to the passive. Ivern currently simply does not appeal to me or any other previous Ivern players. If they find out something is too strong but not relevant if it is getting nerfed then they should rework it or replace it in some way to fix it. I mean for example the point of a shield is to help you prevent damage, if they make a very small shield then the ability loses its purpose. Or if the passive makes him more vulnerable early game he has a strong weakness already that the enemies can exploit, most junglers are very strong especially early so he is technically screwed. I find him as a nice champion though as an idea but in practice currently not as appealing to play as.