honsetly i think that if i'm chain CC'd for 5+ seconds and i die for that it's because of the CC being too strong,not the damage being too high
again most of the "instakills" that we see could have been prevented if the victim wasn't CC'd and took a whole rotation without fighting back/dodging (i know that's not what it's causing this issue but let's take lux as example since what i'm saying it's more clear in this case,she have a strong burst but she wouldn't be able to instakill people if she couldn't CC them before her combo,just think how much damage she would deal without her Q snare)
sure when you are a squishy champ as long as you don't get ANY defensive item the damage fells really high,but when you start to build some defensive item (let's say
which allow you to take a full rotation from a mage/AP assasin and survive with no efford) and you see that they don't oneshot you anymore
when you build full glass cannon you oneshot and get oneshot,when you don't you can survive,i don't like it either but it needs to be like that or else any defensive item would cripple too much burst champions (mostly mages and assassins),so if you think that damage is too high reduce the power of defensive items and then we can reduce the offense as well
anyway as someone said before it could be both things,but (and i know i'll get a lot of hate for that) i'd rather play in a damage meta than a CC one,nowdays most of them are displacements so you can't even cleanse/QSS/reduce them,also they have way less counterplay than damage
once you got hit by a damaging only ability you can still try to dodge the next one or fight back,but if you get CC'd you can as well leave the keyboard,the next CC is guaranteed since you can't do anything in this moment
even worse when they guy who's chain CC'ing you is someone who's playing really bad,didn't do anything the whole game and hard fed but yet can stop you because CCs don't need to scale with your stats or anything like that,while if you snowball a champ that only deals damage you make it useless for a while