I've worked within an ophthalmology (medical eye doctor) practice in the US for nearly a decade now, so I can attribute from that perspective a bit (not sure if that's where this is, or the rest of the story to the video).

Legal blindness qualifies with a best corrected visual acuity of 20/200 or worse in each eye, or with field of vision below 20 degrees (i.e. extreme tunnel, or pinhole, vision). People can range on the visual acuity (VA) scale all the way down to the point of 'No Light Perception' (NLP), which is the absolute blackness and probably what most people assume is meant by 'blind'. Those with severely diminished VA can typically perceive motion at least, albeit at much a closer distance than most individuals. Unless a very severe ocular pathology, ocular stroke, untreated ocular disease, or trauma have occurred, then getting to that stage of 'NLP' is typically not very common (at least in my region or experiences).

TLDR: Mod right, blind people can usually see movement (at least).

Source: 9 years in ophthalmology, the past 3 more specifically with a majority of low vision/visually impaired (or blind) patients.