This is not even a prototype but just a result of running 3 git annex commands (check git history for datalad run records) to fetch 3 sample channels of intrest.
ATM to download actual video you would need to have youtube-dl installed and invoke git annex with special option to allow download from/through potentially dangerous media, e.g.
git -c annex.security.allowed-ip-addresses=all annex get ReproNim/How_Would_ReproNim_do_That_.m