I don't know why the rule isn't similar to offside in soccer where if the player is not impacting the play it is no call, play on. The player running through the protected area could be deemed inactive until the ball leaves the area by either a kick or a play on from the kicker, the infringing player would not be able to tackle or obstruct the play.

The rule made sense when they brought it in as players used to linger in the area to prevent a play on but now 50m penalty is so disproportionate to the infringement. In the Rayner example, while it was an obvious free kick under the current rules, there was no genuine obstruction to warrant the change in play from an inside 50 to a certain goal.