Well I'm pretty sure Ehlers also won't be scoring at a 2.0 ppg pace at the NHL level anyways so I wouldn't worry about some of those things. Nor would I hold him to that sort of standard. I don't think anyone should watch a junior prospect and think, "he won't be able to do that with regularity at the NHL level" because it's pretty much a given at that point.
On the flip side one could look at a player who plays a totally different style of game and think, "well Nick Ritchie probably won't be able to simply run NHL defensemen over 3 times a game when they're all the same size or bigger than him".
That being said Ehlers will split defenses and blow by NHL defensemen at this level with some regularity, I can guarantee that.