Even if it did circumvent copy protection (I don’t think it does?).. the code itself needs a user to execute it. Isn’t this how LAME was able to exist without violating mp3 patent laws?
Section 1201 prohibits making circumvention technology available to others. Sharing source code, or binaries, that are "primarily designed" to circumvent copyrighted works arguably violates 1201. It is not a defense to assert that no one ever used what was shared.
An MP3 patent, such as 6,009,399, covers methods and apparatuses for encoding a digitised audio signal. Writing source code that uses a claimed method is arguably not infringment but as soon as anyone besides the patent owner or her licensees compiles the source code and tests the binary, then there is a much stronger argument that infringment has occurred.
That was their argument, but I strongly doubt it would have held up had they been sued (particularly in the US). Also, a major point they raised was that they did not distribute LAME in executable form.
What/who does the "You" in YouTube stand for. From where I sit, it never stood for RIAA members the commercial works they profit from. Recall the Time magazine "Man of the Year" cover many years ago circa the debut of YouTube. It was, IIRC, supposed to be mirror. The "you" that was named "Man of the Year" was not meant to be a RIAA member corporation. It was meant to be an ordinary, non-commercial internet user. The entertainment industry has "taken over" what I thought was a resource for non-commercial internet users to share video. Here we are seeing the resulting effects of acquiescing to that "takeover". I would guess most content on YouTube is in fact non-commercial, true to the website's original purpose, which arguably makes youtube-dl useful for non-commercial purposes. However, it seems that is not what Microsoft thinks. The (passive-aggreesive) "corporatisation" of the internet (via the web). Lame.
The non-commercial content on YouTube is decidedly not the content which is protected with the copy-protection which the RIAA is (presumably) alleging that youtube-dl circumvents.
It's frustrating because the RIAA is not just requesting that the "infringing" part of the tool is removed. They want the entire tool removed, even for the parts which there is no question of infringement. For example, the 100's of other websites that it works with.