Tank durability really needs to be addressed.
Not only are tank items the weakest they have ever been, there is way too many anti tank tools in the game. So the game changed from "tanks get outscaled slightly late game because they have to build for both resists while carries only have to build for one damage type." to "tanks get blown up every fight unless they are ahead." This has led to tanks being a feast or famine role. Many tanks have started to go with more offensive builds because that is their only chance and even then they have to snowball to make it work.
,
or
with
. It takes a while. Even Vayne needs 2 more autos to deal with that.
:
. That tanky girl is way harder to take out than some Maokai or Ornn building just armor/hp/mr. You need stuff like self healing, shield, Regen, flat mitigation, tenacity, revive, etc. without dynamic defenses you die to true damage like all the rest.