The reader's ignorance isn't implied at all. If anything, that video is a concise, entertaining way to prime someone for the post's topic. This isn't some op-ed in the New York Times. With all due respect, maybe introspect your reaction.
you asked where I got it from, and I explained succinctly; I think my answer was adequate and is a perfectly valid criticism. That you had a different reaction does not require introspection, nor does it require me to be wrong. i hope you don't go online just looking for agreement all the time.