There is something wrong when engaging on the ADC from bot, the ADC from top 3 shots you instead

TLDR: The Current state of defensive stats is total ass and AD damage is way to high

That's what happens when you nerf every armor item in the game of course, but that's gonna be the state of the game for the next two-three weeks, two ranged Carries a game, zero defensive stats and everyone playing rocket tag. Currently who ever has more "marksmen" wins the game, cause it's impossible to effectively build against them, especially since Crit is on everything now and all their abilities hit hard as fuck now. Pretty much anything that is AD with more than 400 range needs to be toned down right now.

Basically you need to heavily tone back the amount of Crit in the game right now, it's way to strong and it lets ADC's reach their power spikes way to early creating insane snowballs. Frozen Heart and Randuins both getting nerfed, Thornmail still being awful, the only real armor item is dead mans plate and that's mostly just a giant wad of health. So instead of tuning armor items up, tone Crit down.