I don't know why you're looking at this season, when the two seasons Liverpool lost by a point were 18/19 and 21/22.
So here's a link to the most commonly played players in 18/19 and then the bench
https://www.bdfutbol.com/en/t/t2018-192002.html
The average bench for city that year had de bruyne, mahrez, foden, kompany, otamendi, Jesus, zinchenko, claudio bravo, danilo, Delph and mendy.
Now maybe you'd say that isn't that strong a bench, I'd say that's a first xi that would get close to 90 points
For reference the first xi was ederson, walker, stones, laporte, gundogan, David Silva, bernardo Silva, fernandinho, sterling, sane, aguero.
Now OK that isn't the first xi it's the 11 players who played the most games. But if you can look at that and say that isn't strength in depth or a significant advantage then there's no point having this debate because you'd clearly argue black is white if it pep look better