You can circumvent it using the inspect element feature of any modern browser.
yt-dl "cirucmvents" it by executing the javascript (the same thing your web browser does).
At this rate V8 is going to get DMCAd for the same reason.
Pretending yt-dl simply does what YouTube does is obviously not true either, because if it did, then yt-dl wouldn't exist. The copyright holder decided he would allow the streaming of the work, if you want to download it you should either get the ok from the copyright holder for that or choose another work to download, or even make one yourself. V8 doesn't change that.
No, it means "in an effective manner"; that's also how it is specified in European legal languages (which have more different words with less ambiguity); the effectiveness must be an objectively ascertainable characteristic of the technology, not simply an (unsubstantiated) claim by the claimant; A "mock protection" would not be protected by the law.
> because if it did, then yt-dl wouldn't exist.
You mix up design decisions made by Youtube with copyright law. Even if Youtube requires users to not download videos in their terms of services this has nothing to do with copyright law and the DMCA based actions.
Technological measures shall be deemed 'effective' where the use of a protected work or other subject matter is controlled by the rights holders through application of an access control or protection process, such as encryption, scrambling or other transformation of the work or other subject-matter or a copy control mechanism, which achieves the protection objective.
DIRECTIVE 2001/29/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 22 May 2001 (see https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A...) article 6, paragraph 3: what you quoted.
RICHTLINIE 2001/29/EG DES EUROPÄISCHEN PARLAMENTS UND DES RATES vom 22. Mai 2001 (see https://eur-lex.europa.eu/legal-content/DE/TXT/?uri=CELEX%3A...) Artikel 6, Paragraph 1: quote "gegen die Umgehung wirksamer technischer Maßnahmen", Paragraph 3: "Technische Maßnahmen sind als „wirksam“ anzusehen, soweit die Nutzung eines geschützten Werks oder eines sonstigen Schutzgegenstands von den Rechtsinhabern durch eine Zugangskontrolle oder einen Schutzmechanismus wie Verschlüsselung, Verzerrung oder sonstige Umwandlung des Werks oder sonstigen Schutzgegenstands oder einen Mechanismus zur Kontrolle der Vervielfältigung, die die Erreichung des Schutzziels sicherstellen, unter Kontrolle gehalten wird.
DIRECTIVE 2001/29/CE DU PARLEMENT EUROPÉEN ET DU CONSEIL du 22 mai (see 2001https://eur-lex.europa.eu/legal-content/FR/TXT/?uri=CELEX%3A...) Article 1: "le contournement de toute mesure technique efficace" and "Les mesures techniques sont réputées efficaces lorsque l'utilisation d'une œuvre protégée, ou celle d'un autre objet protégé, est contrôlée par les titulaires du droit grâce à l'application d'un code d'accès ou d'un procédé de protection, tel que le cryptage, le brouillage ou toute autre transformation de l'œuvre ou de l'objet protégé ou d'un mécanisme de contrôle de copie qui atteint cet objectif de protection."
plus another 22 translations.
German national law: "Wirksame technische Maßnahmen zum Schutz eines nach diesem Gesetz geschützten Werkes", see https://www.gesetze-im-internet.de/urhg/__95a.html
Swiss national law: "wirksame technische Massnahmen", https://www.admin.ch/opc/de/classified-compilation/19920251/...
So the laws in general only apply to technical measures objectively (i.e. corresponding to the state of the art) able to protect legal rights in an effective manner. Measures which are not considered effective cannot claim legal protection.
"technological measures in effect" (as you proposed) means "technische Maßnahmen in der Tat angewandt" in German or "les mesures technologiques en vigueur" in French which is not the same as "wirksame technische Massnahmen" or "de toute mesure technique efficace" or "effective technological measures"
The whole point of youtube was to make it convenient for decentralized content creators to share things. Most WANT their stuff being downloaded. If I'm uploading an educational or family video to Youtube, it's because it's a convenient way for others to watch it, not because I want to maintain control, or earn $0.0001 in ad revenues for Auntie being shown a Trump campaign ad.
youtube-dl makes it possible for kids in the developing world to watch educational videos, for people to watch family videos in rural America, and for kids to learn remotely.
Youtube-dl doesn't do what Youtube does. What it does is extends Youtube to millions of people without high-speed internet connections. That's not a population Google particularly cares about including (not a lot of ad dollars), but it's also not one Google particularly cares about excluding (they are not douchebags, like the RIAA).
If the RIAA wants locked-down controls, they should go with centralized platforms. That's what they're there for. In the meantime, shooting educators using Youtube in the foot means, eventually, educators will go somewhere else.
He discusses exactly this issue, and points out that it does not matter how strong the protection really is...even if it's a basic obfuscation that could be reversed with a one-liner, it still qualifies.
You can watch it here: https://youtu.be/wZITscblMBA?t=889
In short, even though the above comment is being downvoted, I think it is correct from a legal perspective, in the sense that even YouTube's basic approach to obfuscation will be sufficient to quality.
But in the case of youtube, it exists to automate what can trivially be done by hand using the inspector. Seriously, yt-dl really does just selectively run some javascript which gives it the video URL.
I disagree that "effectively" means "in effect", it's the first time I've heard of this and in past court cases regarding such protection measures, the plaintiff had to prove that the measure was effective (not trivially bypassed by an unskilled average user by accident as I think could be argued in this case).
Regarding your claim that I am "pretending" that yt-dl simply does what YouTube does: When I go to the inspector and find the URL for the video and audio streams, without prior knowledge that youtube is using some kind of "rolling cipher" I would have no idea that there was some kind of protection in use. I can access the video stream of a youtube video using just my mouse, I don't have to run any functions or find any decryption functions. You should try it. It's hard to argue that there is a protection mechanism in place if someone could by accident discover the video data if they were a curious user who started playing around with the inspector console.
Finally, to address your implication that the tool is designed to unlawfully acquire content from youtube. I don't think the tool is intended for that purpose, at least not the way it is presented. I think it's important to distinguish between "downloading with intent to keep" and "downloading with intent to temporarily access". I'm not sure if such a distinction is ever made in the courts but it should be considering the former may be illegal depending on whether you asked the copyright holder if you can do it and the latter is literally what your web browser does. 99% of the time I use youtube-dl (which is also the way it gets used by programs like mpv or the kodi youtube plugin), I use it to access and temporarily view a video. I may be on a machine where having a full fledged web browser would be impossible because of performance reasons or whatever. Or I just don't like the youtube viewer and want more control over the playback. The project also codifies in multiple places the intention that it is not designed for illegal use. Extractors which bypass DRM or access control measures are not accepted.
If you look at the implementation of youtube-dl's youtube extractor (please do, the code isn't that complex) it is easy to claim that: youtube-dl is simply a very heavily stripped down web browser which is intended simply to provide the ability to view videos and audio streams on websites with minimal overhead without any intent to circumvent any protection schemes.
As a final note: youtube does have DRM protected videos which use some kind of encryption, these do not work with youtube-dl, I tried (and I paid for the video not knowing that I would be stuck with it being encrypted unless I had EME enabled, in a last ditch effort to watch it I tried youtube-dl but it had the same problem, I got a refund).