Why nerfing adc items is pointless.
ADCs are the one class that doesnt change their build at all. They capitalize on damage and try to build as much damage as possible. Now heres the kicker. The meta adc will almost always be the adc that deals the most damage. This is because of the role concept itself. Youre supposed to deal the most damage possible in the shortest amount of time unless youre varus. Varus
somehow becomes meta off poking or taking 5 years to murder an entire team of tanks.
Point is nerfing adc items will only hinder the items on other champions. Lets say you nerfed guinsoos. Well now udyr and yi are worse but so is kog and varus. However now xayah and draven are the overpowered adcs. So we nerf infinity edge and static shiv. Now cait and varus are overpowered. Nerf lethality and it goes to another adc set. So nerfing items only hurts other roles.
So the only solution is to find a way to make their damage less important to the role of marksman. Its actually really simple to do this. Make non adc lane bullies for the bot lane.
If adcs arent allowed to effectively farm on the bot lane they will be forced to go mid or give up their role entirely. Trust me adcs will always exist in this game unless you want world of tanks the moba. So if the adcs are forced mid and the bot lane becomes wizzards vs juggernauts, they will have to have 1v1 capability. This means their dps will matter less and utility will matter more. Sure certain adcs will still be damage and not much else
and still be viable. But sivir will also be viable because of her en mass amount of utility. Ashe will also become viable due to her cc. This will mean that the philosophy riot has been trying to push will be effective instead of "what deals the most damage."