Like others have said, 120 hz is needed more on a device like a phone where you doing a lot of scrolling and moving around, so you're going to notice it a lot more. Hopefully nobody is getting a MBP solely because of the 120 hz display and not for the other benefits the MBP provides. If that is the case, they can save a bit of money with the 60 hz screen MBA which in my opinion, is still fine for basic tasks that most people would use it for.