So lets find the solution for our Riot dev team.
So, as we all know, the game is garbage because of dmg. But there is one big PROBLEM
Tanks need to be tanky AF in order to be useful as tanks alone soaking dmg for their teammates. Adcs need to be oneshotted by assassins ( tbh, they need otherwise there is no other way how to kill them), but if tank items are going to be OP for tanks then those adc will be able to outlast that oneshot and then will via big DPS combined with lifesteal wreak havoc. ( 1 tank item would be enough if tank items were good enough).
Tanks also need have their dmg be lowered, since even they can quite well chunk squishjy that is just a little bit behind. Assassins need to be able to do their thing as they do now but should be less reliable or have higher conditions or have trade off in term of CDs or something so that they arent that they wont be able to do much to champions that outlasted their combo and arent that strong on longer run. ( Both, ad and AP champions). Example of this is Zed who use WRWEQ F/R and then the other one and then E again and finish you with autos or goes back and forth and do WEQ combo.
This is the holy trinity ( Tank>Assassin>ADC and ADC>Tank). The problem is that if DMG in game get lowered then ADCs and another DPS monsters will go rampage. If Assassins get higher dmg to stop them then tanks will be left behind. If tanks get high base stats ( so that their items wont affect other classes) then they will buy DMG item and get transformed into juggernauts with better CC, shields and etc.
Whats your solution? Is it to force classes to buy what they should by scaling? Should tank items be bit stronger but lower base dmg of non tank champions to lower their cinder-hulk potential in comparison to real tanks while lowering scaling of tanks to lower their full dmg potential in comparison to real dmg dealers?