Nerfing the items and talents also affects the Champs who are just fine with them too. Usually worse than it it affects those the nerf was originally aimed at. Nerfing tank itemisation is just going to force tanks out of the meta entirely, as a role they come and go largely based on the strength of their items. Ekko and Fizz would be forced back into their intended Assassin builds and would keep performing well, it wouldn't really "fix" the problem at all.
Realistically Riot needs to take another look at Ekko's kit and decide if him being an Assassin is the best fit, unfortunately if they do they're going to upset players by forcing him out of one of his builds. He's not the only one, Diana could really use another pass too, as could Akali, Fizz one or two other outliers. AP Melee update when?