You can’t just add muscle to Milan and change him into a different player. He’s tall, but he’s not a paint banger and adding muscle isn’t going to suddenly make him an athletic rebounder. He’s a pure shooter and that can work if you can get him looks and he’s having a good night hitting shots. He didn’t hit the few get got tonight. When you lose a 6’9” AA, that makes it even easier for a team to defend Milan.
Can’t blame Milan, you could make an argument that the coaching didn’t scheme well enough to get him more looks, but you can’t blame him not being a rebounding machine in the paint.