With most companies, Hanlon's razor would probably apply ("never attribute to malice that which is adequately explained by stupidity"). But in this case it is rather dubious (if not shocking) how GitHub's legal department appears to have completely failed to do their basic job.
As a company, GitHub at least has a legal duty to know the law, or be held accountable for the consequences of their actions when they monumentally fuck things up (while doing serious harm in the process).
Either way .. with Microsoft's track record in mind, GitHub's silence on legitimate questions regarding the validity of the RIAA's actions, and now this warning of inflicting harm to people if those dare to not play along with the companies dubious legal decisions .. all in all, I'd say that GitHub has long lost any benefit of a doubt by now.
With every day passing, this appears to be shifting more towards plausible (if not likely) malice. On top of that, this isn't a light matter either. Most likely a serious anti-trust violation and might even constitute a criminal enterprise. Not that I expect US authorities to do anything about it, considering its own dubious and dismal track record, for at least several decades.
0: https://joindiaspora.com/posts/808cf690f8e801381778002590d8e...
From a formatting perspective, format is generally irrelevant to notices like this because the law does not state a particular format must be used. Thus, any format which conveys the necessary information is generally acceptable.
And while formatting is somewhat irrelevant from a legal standpoint it is still one of the tools Github uses to ensure that their take-down requests contain all the required information. Acting upon a request that doesn't conform to the format is risky.
How far do you think I'll get if I tried to file a bogus DMCA request for a Microsoft repo?
It happens that they own Github, but s/Microsoft/Oracle/ and you'll probably get the same result.
The automated systems will take down the repo for a bit, then the owner of the repo will kick your ass in court.
It just happens that youtube-dl doesn't have a large corporate owner, and the RIAA _is_ a large corporate entity, and so this is how it happens.
Your anger is misdirected here....
No service provider is going to fight a specific case of DMCA for a third-party.