Riot nerfs tank items because they don't like bruisers being tanky and doing tons of damage. Riot doesn't like it when tanks build damage.
Fine. Make tanks tanky by giving them percent bonus scaling on their defensive stats so that they scale better with tank items.
Do this, and tanks will build tanky and not offensively, bruisers won't abuse tank items, and tanks will last longer in fights.
oSEXYPLATYPUSo2 votesbruisers will still have tank items
they have to by design in order to sustain enough damage to do damage
tanks have to have soem damage to be a threat other wise they will be flat out ignored in any fight situation
Great Ozymandius1 votesI agree that bruisers need tank items. But many tank items are balanced around bruisers (and assassins). If the tank items are strong enough to make tanks feel legitimately tanky, then the bruisers (and tank-build "assassins") break the game.
The point is that riot needs to seriously consider adding percent-scaling stats to classes. Riot wants to make the subtleties of a champion's kit and the subtleties of available items result in the "right" optimal choices (tanks building tanky, adc's building squishy with crit, bruisers building a mix of tank and damage, assassins building pure damage, etc). It would be nice if Riot could do it. But they can't. They just need to face the fact that they have not choice but to balance the game in a heavy-handed way.
oSEXYPLATYPUSo1 votesbut most champs if they build mostly defensively looses out on damage
and if you build mostly damage you lose on defensive
there is a trade for everything
like if fizz was to build tri into tank and triforce his is only item then his ability to one shot and blow people up is nearly gone however he is a bitch to kill and in a extended fight as that fuker flops around he does more damage over the extended fight cuz u cant kill him
its not that he has more damage... its he survives longer therefore through extended fights like juggernauts and tanks that is where their damage shines... they arent blowing you up... but they are doing damage over 10+ seconds of a fight
Critmaster Garen1 votesthey didnt want to hit bruisers with the item changes. at least i hope so, because it would be stupid considering theyre designed around at least partially building the same items.
they wanted to prevent shit like bruiser assassins/melee carries 
and bruiser adc (mostly) 