Riot what role is Zilean supposed to fill now?

Like to understand what role Zilean is supposed to fill now bot lane as support since he does not have reliable poke...truly any poke? Some guy is gonna write how awesome his zoning is now but what is the fun in throwing out bombs that just make it hard for them to move forward for 2 seconds? I think you have ruined Zilean especially in solo q. If you have good teammates I think Zilean can make a contribution with the slow and speed boosts and his ult but if you don't you are irrelevant to making a difference in a game now. I saw a lot of people write that Zilean had no counter play with his bomb, but he is very squishy and he can be itemized against if people play smart. He was a stick and move champ that had a really fun kit because he could do a lot of things. I am not happy about this change. He has no place in the game anymore for me. If you want feedback, mine is to find a way he can do meaningful damage. He is a mage support. Take away his damage and he is lame.