The way the video showed the lectern light going out looked much more like an LCD display behaves, it’s more than a simple lamp. The turning off has a ramp down period where the edges decay at first before the backlight goes completely off. I’ve worked on a number of computer display drivers and am used to seeing this effect - I swear it is some sort of display.
...although to your point, it did cross my mind too - perhaps having a constant light on her helps with not getting “triggered”. Maybe it’s both :)
What I gleaned from the ‘light therapy’ treatment made me think that was the case with Clinton.
[ This “light” approach is particularly appealing in Parkinson’s disease because patients commonly suffer from excessive daytime sleepiness, fatigue, sleep disorders, as well as depression—and all have been reported to potentially improve.]