Better tank item at the cost of a draw back to dmg output.

Tanks being both difficult to kill while they are killing everyone should not = nerf their tankiness. Being difficult to kill is what they are supposed to be doing, what should be fixed is the dmg they deal. Of course you dont want to make the champions unable to deal dmg by defualt or they cant farm effeiciently which is why sunfire doing more dmg to minions is a thing. Making any one tank item too good means a tank can afford to get more dmg allowing them to be both unkillable and have high dmg. This also means nightmares like tank Ekko can exist.

I think a good way to have a really good all around CC tank focused item is to make it so the buyer does % less dmg to enemy champions that effectively negates the additional tankiness it gives them in a 1v1 situation. Basically leading to the result of them both taking longer to be killed and they take that much longer to solo kill an enemy as well. Similar to this items active only not scaling/less extreme all the time while one has the item.

60 armor, 60 magic resist, 500 hp, 500 mana, and a 20% CDR passive for 3k gold is OP unless you also make it so the item makes the purchaser do somthing like 20% less dmg to enemy champions for buying it(I dont know if this is good, bad, op, or weak. I am just trying to get the point across). If the best value a certian tank can provide to its team is to take dmg and CC enemies then such an item should exist with this soul function in mind. If it empowers the tank too much to the point they can win 1v1s with pretty much anything early in the game then dont take away the tankiness of the item, thats the whole point of it. Just make it so a champion does less dmg upon purchase to counter act this.