GitHub can't, until at least the the public support is in their favour, because legally it's a hot water. This is not your ordinary copyright DMCA Complaint, this is the section 1201 concerning circumvention, which is held to a different standard. This is essentially RIAA telling GitHub "if you're not stopping this, we'll see you (not the YT-DL developers) in court".
> GitHub can't, until at least the the public support is in their favour
Public support on which grounds?
I can’t see any evidence a counter notice was filed until the EFF got involved, at which point GitHub immediately reinstated YouTube-dl.
Did GH ignore a counter notice?
twitch actually does do that IIRC, not sure about others