The discount will be duplicated on all platforms, over time and on sales the price will drop, so that more people can try the game.
+ Steam helped to adjust regional prices, maybe in your region it will be cheaper.
(This is the price for USA, with tax and share that will be taken by steam ( 30% is taken by steam + 10% is taken by USA for our country of residence and the remaining amount we will have to pay tax :D ). That's if it's very short and clear.....