I disagree that they don't think it abrogates rights. I mean, their words, again:

[Proposition 8] carves out a narrow and limited exception to these state constitutional rights

If equal, rather than separate-but-equal, wasn't a right, they wouldn't be talking over and over again about how it carves out an exception to that right, but that's okay.

I think they've opened up quite a can of worms here.

The plaintiffs had made the separate-is-not-equal case in the previous ruling that legalised marriage to start - it was the crux of winning that case - and leaned heavily upon that decision made by this same court. So, essentially, yes.