Obviously that was a factor too, but he was definitely missed from the midfield, it was notably a weak point that season, I said so at the time.
Liverpool were a team at the height of their powers with several other players performing at a world class level so they'll have coped better for sure, but it's not to say he wasn't missed in those games.
In the same vein we'd probably cope better without Partey this season than last, especially if Zinchenko is fit in the games he misses.