Seoul won because the coaching staff allowed the players to play the heroes they are known for, and as a consequence Seoul was able to take down the Shanghai Dragons, who is arguably one of the top teams in the league right now.
Chengdu tried to put Ameng on Orisa and he was picked off first every time by London on Lijiang.
I get that you should be versatile with different heroes, especially in the age of hero pools and role lock, but there is a reason why most players have a certain hero that they “main”…because they know the ins and outs of that hero to the point where they can play it WELL.
I don’t remember all of the nerfs, nor do I have the patch notes ready on hand, but I remember there was a slight nerf to her initial slow, a nerf to the ammo consumption on her primary fire, and there was a nerf to Blizzard on experimental card, but I don’t remember if that change went through or not.