That's not going to change. The midfield wasn't scoring last year either and it won't this year. Their job isn't to score. That's quite clear by now
I think it's misleading to assume that just because our midfield didn't score last season it thereby means they're not set out to score.
Certainly, Henderson, Milner, and Wijnaldum aren't going to score goals, but that's partly because of their profile.
I'm fairly certain had Oxlade-Chamberlain and Keita played (or were available) for the majority of the season than we'd see the goalscoring stats increase for that position.
I think it's more accurate to say that the way we play, and with the attacking three that we have, that a midfield that doesn't contribute in scoring isn't going to be a potential key obstacle for us to win. But it doesn't mean we're not set up for the midfield to score. It's why we brought in Oxlade-Chamberlain and Keita, midfielders with the profile that checks several boxes for Klopp (physical, quick, technical, eye for a goal+pass, quick on the ball,and comfortable making the risky pass, comfortable on the ball under pressure) and unfortunately injuries have prevented us from seeing exactly what Klopp expects from his midfield.
It's funny to think that the players brought in to challenge Wijnaldum, Milner, and Henderson (in his current role), haven't been available for the majority of their time here. Imagine how different our midfield could look or benefit from having both of them healthy and active for an extended period of time.