There's no question that Carlsen has always had Nakamura's number. I don't think any other top tier GM has fared as poorly against Carlsen in classical. Nakamura is still one of the very best speed players in the world but you would never know it when he plays Carlsen.
There is one: Carlsen is 6 out of 6 in classical against Pavel Eljanov. That's 6 wins, 0 draws, 0 losses.
If you include rapid and blitz, Eljanov's score percentage-wise improves slightly, as Carlsen's total score becomes +10-1=2.
Nakamura is ranked 8th and Eljanov 38th. I don't consider someone ranked 38th to be top tier. But regardless, Carlsen has played many more classical games against Nakamura.
Eljanov has been ranked as high as 6th in the past, and in Mar. 2016 he was 11th. He definitely hasn't had as good a career as Nakamura, but he's been a better player for much of his career than his current ranking would suggest.
Carlson: simply the best. Your observation is interesting, but he’s defended his championship twice, and the next one is his to lose, meaning if he plays to his potential, he’s going to retain his crown.