Take Davis's name out of the discussion and imagine the sort of return (goals/assists) you would expect from a player who has played a large majority of his career in the AM/CM position.
Based on that Davis is not giving us the return I would expect in that position but based on value (cost/wage) he is currently above his value in my opinion.
A hard working, assist making, goal scoring CM/AM is an expensive position to fill, it will be interesting to see what the club do.