Yeah, its a completely useless token gesture that exists entirely to put your name to paper on agreeing that "this thing was bad/good" and refusing to sign indicates the opposite viewpoint.

It would have done literally nothing if they signed, so their refusal is full admission they support it or they are scared their own supporter base does and would condemn them for doing so.

Which is even more telling, that they know the Left is feral and dangerous and they'd rather run scared of them than sign a piece of paper.