Personally, I have never believed that Benteke is the main problem. He is part of the issue, but not the main issue.
If you are playing with a target man, his job is to get to the end of crosses, to hold the ball up as the team gets support, and for him to drop a bit deeper as others make runs beyond him.
How many players are consistently making runs beyond Benteke? How many players are making a pass to him, and making a run into space to receive the ball, or making a run when that ball is played to him? And when the ball is played long, how much support is there around him when he eventually wins the ball?
I agree, we're not using Benteke in the way he's been used in the past, guys down the wings, getting to the byline, whipping in crosses for him to attack. He's shown he can put those type of chances away.
So an option is for Klopp to get guys swinging in crosses more regularly, try and use those strengths. And have players supporting, picking up the pieces of Benteke's challenges for the crosses.
Personally I don't like that option though / that kinda game ... it's percentage football, you need to put a lot of balls in to get returns (and is main reason I gave up on BR, when he started long-balling it up to Ben). Much prefer to pass and move etc. high tempo with intensity. BUT it is an option, particularly if we're just not functioning up front in a game.
In saying that, you'd also need the Benteke we've barely seen, the target man who is big, strong & bullies defenders. At the moment, Ben looks 'shy', doesn't look up for a fight and although in fairness to him he has scored a couple of important goals, his general play is well below the required intensity, he's not showing up for a fight, not hassling defenders, dishing out knocks and bruises. Even if not playing well, throw your weight around, fight, cause some F***ing mayhem, be the guy who leads by example, it can raise the team, the crowd.
He has the attributes, but imo he has a real problem with confidence, already with a mental coach, he's struggling to implement what Klopp asks for, and think it's clear the him and us the manager is frustrated. It can be chicken and egg, need the confidence in order to play well, but also need to play well to build confidence. Am not making any excuses for him though, if it's not happening, you don't trot about waiting for something to happen, you need to work EVEN harder, graft and fight, and eventually the chances and the reward will come. And that's what's disappointing, cause not really seeing that. (and in fairness, not 'just' from Ben, but from a few others too)