“Lectern power supply and bmx”
Written on side of wood box between lecterns means?
Electrical / electronic hardware for sound. The mics probably need power to work, and "BMx" is a model name for a sound mixer.
I don't think there is anything particularly unusual in the stage design. Teevee and movies are all about creating illusions, and the illusion being perpetrated here is that the candidates have approximately equal physical stature.