When I tried using aria2 to work around the throttling you mentioned, I noticed that simply using aria2 at all (no parallelism with -j/-s) fixed the download rate. The primary difference was the User-Agent header; the standard youtube-dl User-Agent[1] was throttled, but "aria2/1.30.0" was full speed.
The throttling also seemed to depend on which server was sending the file; a bunch of recent uploads were throttled, while an obscure video from 8 years ago with The throttling problem seemed to go away after a few weeks, and returned again for a few hours a . Is it possible the "throttling" was actually some type of bug or configuration error in Google's network and/or data archives?
[1] https://github.com/rg3/youtube-dl/blob/master/youtube_dl/uti...