I think it's being done to shine a light on the problem. And, possibly, to put a strain on the organization. If WTS is working to protect child abuse just to maintain an illogical and silly rule, then the approach may be to make it as costly and painful as possible to continue to do it.
The WTS will fight this with every resource they have, especially time and money. It is likely that this will move extremely slowly through the courts, and it will seem as if no progress is being made. But I think that, even if the WTS prevails in blocking this (and it might), it will be publicized and their resources will be drained. And not just money-- imagine any elder with even half of a conscience, realizing that they're fighting so hard to protect traumatic child abuse. How many will walk away? How many will talk?