In the maccabi haifa match, he did played bad.
But its the same issue, they played 3-2 zone and had a better perimeter defense rating then your outside scoring.
His game shape is another factor as well, I dont know his game shape before this week's training but I doubt it was higher then respectable.
You didnt show his driving skill, so I assume its not that good. If you team dont have good passers and your sg cant create spaces to shoot, then its no good having a sg who only can shoot