I turn off "natural scrolling" on the trackpad on my Mac, but I don't see the digital crown as the same thing. Technically, a watch crown has traditionally been used for rotation of watch hands only. So, in order to convert that into scrolling content, it's entirely arbitrary. I personally like the decision to mirror the motion on the touchscreen because the crown sits immediately adjacent to the touchscreen. It's an extension of that screen - the same cannot be said for the trackpad on the MacBook or the Magic Trackpad. Location matters.