Tanks

so im a huge fan to playing tanky top laners like malphite maokai ect or just get tanky like with champs like poppy or sion but anyways i've notice how the word TANK seem to be kinda missleading nowdays cause back in the days tanks was supposed to be able to be hard to kill champion who could take damage but nowdays anyone can just melt you like no matter how much armor or magic reist that mid laner adc or top lane ad bruisers just cut you down like no problem what so ever even tho you got armor/magic resist or hp just coming out of you ass and it kinda pisses me off how well unbalance well pen and HP% is like like im a malphite aginest full enemy ad team i got full armor get up to like 500-600 armor like okay nice and what does the enemy team need 1 last whisper or fuck even most cases they apprently need just blade of the ruined king and thats apprently enough with no pen to melt me like 1 item can counter my 4-5 items its like what the fuck?????????