Fun fact, Marksmen use to need 4 or 5 items to start deleting people, now it's just back to that. They weren't attacked, they were just lowered back to where they used to be(At least crit adcs anyway.)
You are acting so defensive by calling it an attack. As for who I would say needs to be toned down next damage-wise? Assassins and tanks, and bruisers, though I don't feel Riot would willingly nerf three, or even two class types at once. Tanks are suppose to be able to tank, right now, if they aren't Mundo, Sion, or cho gath, they get shredded too fast to really be called tanks. If you don't have at least 2 tanks not including one of those three(Sion and cho both can stack health permanently if played right), you might as well not have one at all. Because they'll melt your frontline otherwise. Right now, even tanks have more damage than they probably should. Instead of being about being a good frontline or engage/disengage.