Honestly, I think Roberts would have been the 5th vote in Obergefell if not for Kennedy. This is the same guy who flipped his decisive vote to save Obamacare. He’s a politician, not a Justice.
Frankly, I think Roberts was or is being blackmailed for some of his votes (his being closeted and a dodgy adoption scheme regarding his kids).
I remember in his hearing he would be for the little guy when it was right. Sorry ‘little guys and gals’, not today.