It also depends if the judges want to get into the middle of it. If elected congressmen and senators legislate an overturn of Roe v. Wade, do the judges want to get back into it or will they let it stand, thinking it's no longer their problem and sigh in relief?
To be quite honest, SCOTUS refusing to hear the case, if such a case ever came their way, is something I have never considered happening. How do they decide which cases to hear, anyway? I seem to recall that they turned away one or two high-profile cases last year.