Assassins were never meant to scale, if Zed didnt get the job done by 30-35 mins, the game should be over for them. That was the cost for playing Zed. I even knew that when I played Zed, get the job done, kill every single lane and make your team stronger than the other team and win. But now its what... Their fed? Oh well, ADC cant get into fights without dying even if they play well.
Its either Zed/Fizz players accept QSS countering them late game, or accept the rework, because its already confirm that Zed and Fizz are getting reworks in the near future so they have more counterplay against them and probably removing their debuff and how they get away from situations so they cant go in for free and kill the ADC/APC. So do you want a new playstyle or do you want QSS, if I were Zed/Fizz players I would rather deal with the QSS then having a rework.