Riot has moved on
I've come to the conclusion (wrong or not) that riot is changing its game not around balance but purely to fit its pro scene. what I mean is that they continue to change the game into what people want to watch instead of what people want to play. Riot (Tencent) I believe has intentionally shortened games simply because viewers got bored of watching 40+ minute games. They changed turrets just to enforce the four people in bot lane meta because they felt viewers where getting bored of watching teams just swap turrets (just one example of them changing the game not around balance but around forcing better tv) and now here we are halfway through season 8 and the games are faster than ever. Unfortunately with franchising taking hold and bigger and bigger money moving into the pro scene I think it's unlikely that we will ever get the game back towards whats fun to play instead of what they think people want to watch and to be honest that makes me sad.