Instead of instantly down voting and avoid answering the question
Why should J4s E-Q ignore all CC? Why? For example morg's magical root that's supposed root you in place and he simply ignores it and completes his dash.
What about veigar's cage? Correct me if I'm wrong please, but I'm sure it ignores it too when it's supposed to ignore dashes.
So why should j4 ignore anything that stops any other dash?