I think there is a lot of comparisons being made here that are not on a like for like basis.
Whilst he has given away a few goals, Naismith makes a massive difference to our team going forward, building from the back and always being available with confidence on the ball (sometime over confident!).
Similar can be said for Matty James.
Put Semenyo on the pitch when they are both fit, I will think you’ll see a different player due to the team being more composed with that extra experience and comfort on the ball.
Out problem is the depth…. We don’t control midfield without James, we don’t build from the back and look comfortable on the ball with out Naismith.