>It does do directional steering. No active array components or physical movement are needed.
By... plugging and unplugging antenna elements?
It makes a fixed directional antenna element array which is configurable to a small degree by choosing which antenna elements to connect and their spatial arrangement.
The radiation pattern can only change by physically plugging or moving antenna elements.
It can be changed electronically and is commonly used that way in LTE and Wi-Fi implementations of Beamforming.
> By... plugging and unplugging antenna elements?
No. The antenna elements are always plugged in the same way. By sampling/introducing the signal at a different physical position on the lens (or multiple positions simultaneously), you create different physical distances and phase shifts for each element, and therefore a different beam direction.
...Apropos of nothing, this reminds me that a long ago, I played on a Minecraft server where one of the boys made a piston display with controlled by a pressure plate array. I was shocked by how he managed to transmit the signal with a simple wire. Maybe it was a similar idea, using the propagation distance...