Noone bans the cow, its a wasted ban, theres better supports like Lulu or (atm) Taric
he's also getting a minor buff soon.
The changes to his W are actually going to make him alot less useful. The reason hes so popular right now is because everyone stacks health and armor against shredders so you take supports like Taric because his W at 5 right now gives you a whoopin 30 armor (thats why you see Jarvan + Taric alot, your team gets 56 free armor every teamfight, thats dumb. Buy an Aegis on Jarvan and thats a grand total of 76 armor that your 4 other teammates get for free, what the... riotpls). When the patch hits you actually have to hit 300 armor on him now to hit this value, and without gold thats impossible. He will be a better solotop with these changes, especially his new passive, can see Frozen Heart being a core item on him now.