Ok, so is it a foul if you clip someone's ankles before playing the ball during a tackle?
Did you think Lloris was fouled yesterday when he went up, claimed the ball, and was bumped, making him drop it?
It doesn't make jumping higher illegal at all. You can of course, totally legitimately get higher, with bodily contact and it be completely within the rules. What you can't do is connect your elbow with someone's head (before or after the ball). There is a clear difference.
If you can't make contact with the ball WITHOUT going through the player first it's a foul.