It’s a light for a speaker’s notes. Trump didn’t use his.
No, it’s not.
Notice the piece of wood in front of it to obscure it from sight of the cameras? But the cameras were high enough to see the light anyhow. There is no way that any light could shine on any notes on the lectern because that baffle would block the light. Watch the video and notice the light is going on and off all by itself. Notice that people afterwards were removing many items from inside of the lectern afterwards then hiding them, what appeared to look like batteries and other devices. Notice none of this was being done on Trump’s lectern? Nope, this appears to be a device to cheat.