Ok first of all I like the changes to most of the assassins, however I don't like the huge power spike assassins got. This preseason update basically means that adc's are useless in soloQ now (except for botlane urgot). We already know that riot only balances this game for competitive play and doesn't care to much about the rest of the community. So we'll probably see changes when spring split starts.
If you're playing a adc in this meta you're either mad or a masochist. getting bursted down in less than a second by a single attack or ability leaves no room whatsoever for any counter play, especially when those assassins can basically go half bruiser and still deal tons of damage. If they want to do a lot of damage that's fine by me but than they need to trade sustain for that.
It's the same problem we saw with tankali. Why was/is Akali able to go basically full tank and still deal a lot of damage? Because damage items are to effective, they simply give too much stats. So to be honest it wouldn't surprise me if adc's are starting to do the same thing build 2-3 damage items and the rest defensive. It's the only way to be able to do anything versus assassins at the moment.
I get it, Riot thinks they need to do something unique each season and this is the assassin season. Here's an idea for season 8: Balance the game, balance the items (and give us more items cause actually there're not a whole lot of different options).