This lets you run a dual power supply, and keeps them far enough apart that they don't interfere with each other's air intake. The round shape is there to give it structural support, but happens to bear a resemblance to a certain ring wielding superhero's logo.
Dual power supplies allow you to run the servos/mainboard on one and the hotends/bed on another, through external mosfets, and to use hybrid voltages ie 24v / 12v.
Print the bridge part on its side so you don't have any supports. I ran out of screws, you'll need 4 m3 16mm and 3 m3 6mm in addition to your original hardware.
This design will also let you straddle a vslot with two supplies.