It would be interesting to hear all those who complain about Lindelof's aerial ability, who they would like to replace him with. Of the most common suggestions, I wouldn't say anyone is an upgrade in the air. Here are aerial wins per game this season:
Kounde 2.9
Lindelof 2.6
Konaté 2.6
Upamecano 2.4
Varane 2.3
Ramos 2.0
Pau Torres 2.0
If we make a list over won aerials in the PL, Lindelof shares position 22 out 49 CBs, so slightly above average by PL standards. (CBs who played more than 10 games).
One difference is that we get better result in big matches with Lindelof as CB.
Lindelof has 5 big matches in the PL this season (Chelsea, Liverpool, City, 2x Arsenal). We have 4 clean sheets in those 5 matches and totally conceded 1 goal.
Bailly has played 2 big matches (Tottenham, Leicester) and we conceded 8 goals.
It is obvioulsy not only becasue of Lindelof, but our defence has looked well organised in the big matches he played.