After Carlsen was excluded from the 2021 FIDE Rapid championship playoffs by the Sonneborn-Berger tiebreak, chess24 reported:
He (Carlsen) criticized the rules, saying it would give his opponents an unfair advantage as long as he is the highest rated player
But Sonneborn-Berger does not take rating into account, so how does it give an unfair advantage to lower rated players?
Update: @Alexander Gardens points out the quoted complaint is about Dubai 2016, not the Rapid World Championship 2021. I suspect that clarification in the linked article was added after I asked the question - maybe someone with better Google-fu than me could confirm if that is the case.