Okay I watch the video, it doen't demonstrate the earth is flat. He shows what one would experience if the earth were flat. However we do not experience that.
The video is entertaining and does a good job explaining why the flat earth thing is nutty, but doesn't really refute the flat earth claims. (That is likely because the flat earth claims don't make scientific sense and are based on experiments not testing what they are designed to test)
I'm assuming this is your first foray into Vsauce. It's a quite brilliant channel. This video is one of his earlier ones, but Michael has fast seasoned into one of the best science communicators on YouTube, and overall, for that matter.
I honestly don't watch YouTube science videos, so yeah first time watching this man's series. May have to look into some more as it was entertaining at least. :D
agree, i never watched his earlier stuff but his vvideos are excellent! millions of views / video for science