Buff Tank items/Nerf Armor pen Items

So i played a game with Shen in the top lane,all good early-mid until the enemy Mf bought Youmuu+Black Cleaver,enemy master Lord Dominik's and Jayce Black Cleaver + Lord Dominks and I suddenly became useless.I had 350armor 3.5k hp and i still died in like 3 seconds. I build 5 out of 6 items full tank and i still get pretty much one-shot? How is that even fair? What's the point in playing tank champions any more(except Tank Yas and Ekko) if you still get killed almost instantly if focused. So like i said in the title either nerf armor pen items or buff tank items somehow.To be fair you'll need like 500 armor to really be a tank vs fcking Lord Domink's and Youmuu +Black cleaver builds.