My guess: They want the wind to pass through the crane, while they want wind turbines to capture the wind.

This is the answer.

Interestingly, wind/storm loads are oftentimes the limiting factor for the configuration height of a crane.

This is because, when adding another tower segment, not only the total area increases but also the wind forces. The other loads stay roughly the same

This is the reason why bottom-slewing cranes, which are commonly used for small buildings, sometimes are built with solid walls. Top-slewing cranes, which are used for high buildings, always use a steel framework.