Armor only got nerfed all because Juggernauts are too strong with it
Seriously.. it is not like they nerfed Last Whisper or Blade of the Ruined king. So there was no reason to nerf armor so hard other than the fact that Darius, Garen, Skarner, or anyone that buys these
would be completely over powered with good armor. Being in the front line is miserable against a juggernaut, they tank pretty much just as much damage as a tank if not they can with the over powered shielding from
which is pretty dirt cheap if you ask me. There is only a certain amount of peel and CC you can dish out before a juggernaut and his team rip you apart because juggernauts deal a massive amount of damage, while shredding what little big of armor you have with
and you are getting melted by their mid laner and ADC (how do you expect a tank to survive this at all?). And as a losing team going against fed fighters and carries you feel how bad it is because your armor is so expensive and not effective enough for you to last longer than 3 seconds. And when all the juggernauts are banned out (which happens quite often) you see that Armor is a joke because items like
are even more effective than before when armor wasn't nerfed and was still completely counterable.
TL;DR Juggernauts and their itemization are vastly over tuned and it has caused tanks to be hit even harder with even more nerfs to their tank itemization. Being on a losing team or fighting against an AD champion that is fed is even more punishing because you simply cant afford armor when they are just going to buy anti tank shredding items in the first place. Tanks simply get melted and destroyed by front lining against a juggernaut that deals insane damage, soaks a ton of damage and allows the carries to shred through you easily and win like that. There are so many tanks that have been nerfed this season along with basically every single tank item being nerfed it is not a surprised the already over tuned juggernauts are just better at this point. Tanks are in a horrible state right now.