Regardless of any arguments about legitimacy, the optics of the EFF and ACLU defending Omegle against a child sex abuse victim are horrible. They need to raise funds from donors and having to explain that they fought against an individual abuse victim seems like the kind of position they would want to avoid. What I imagine they would do is fight against any overzealous legislation some politician tries to throw together in some ham-fisted response to this kind of situation.
EDIT: Admittedly I know little of the history of these groups. Comments suggest I may be in error on my inferences here.
EDIT: Admittedly I know little of the history of these groups. Comments suggest I may be in error on my inferences here.