The moral of the story, if there is one, is that there’s no real evidence here for any handwringing concerns about backlash. The opinion trend in favor of marriage equality is pretty strongly favorable, and courts should do the right thing.Absolutely. But I think we can find stronger footing for this than a few charts. From the Warren Court onward, there have been numerous decisions that have infuriated conservatives. Miranda v. Arizona (which instituted the Miranda warnings) infuriated conservatives at the time. Baker v. Carr (which eliminated state senate "rotten boroughs") infuriated conservatives at the time. Of course, there was the whole of civil rights jurisprudence of the era as well. Long story short: there was lots of stuff that caused some short-term conservative backlash back in the day.
What happened? Well, conservatives dealt with most of it. Once the idea that abortion was roughly equivalent to murder took hold within the Republican Party, it makes sense that they wouldn't be able to live with Roe. But that is something of an exception--outside of Kelo v. New London I can't really think of an enduring case of judicial backlash in the past few years that might still have some potency--even the Supreme Court's decision to ban child execution several years back has largely become unremarkable, despite some howls of conservative protest (ditto Lawrence v. Texas, the Texas sodomy case). Ultimately, I think the point that needs to be made here is that, if you have the law and morality on your side, there is little to fear from these sorts of court cases. If the law and morality are murkier (and on abortion in particular, the law upon which Roe is based is rather murky), big decisions like this can cause enduring damage to the cause. I've long believed that abortion should have been resolved legislatively, though I agree with most of the actual logic of Roe--it more or less applied earlier precedent (Planned Parenthood v. Connecticut, about birth control) to a similar situation. But an awful lot of people felt left out of the process. And it would have been much harder for the Republicans to assume "ownership" of the judicial issue. It's not like defending disproportional state senates is going to help you own that issue.
Interestingly, I remember reading a book on Harry Blackmun some time ago in which he seemed to think anti-Roe backlash would blow over a few years after writing the decision, like it mostly did with cases like Miranda. Needless to say, he read that wrong.