I am in video conferences all day every day, I easily burn through 1TB/mo without torrenting or warez. I use my internet to work. Throttling impedes my ability to earn.
If I were to watch these videos for 8h in a row it would be only 4GB a day or 86GB for 20d/m. FullHD video. At 60FPS.
Sure, video conferencing is a bit a different beast, because there is no way to compress a dynamic stream so effectively... Except if you don't run you conference from a Porsche 356 going through the woods then 90% of the picture is just walls of your room/office. It CAN run just fine with 1-4Mbps.
Hell, we had a good enough video calls in Skype almost two decades ago, on a meager DSL lines with 1-5/Mbps limit.