Everyone should generally assume that unless you have something tangibly in your hand, you either do not own it or you may very easily and/or suddenly lose access to it. You could test this by trying to access the content without having to sign in to something.
All these streaming and subscription services should be considered ease of access conveniences. In other industries, you pay a premium for something to be prepared for you to consume. In the subscription industry, you’re paying less because you’re not paying for the content but for a license to temporarily consume the content (and probably because your info is being sold to advertisers).
Fun Fact: If you were to rip a Bluray to your computer, you’re legally not permitted to watch that movie if you’re no longer in possession of the disc. This is because you’re not purchasing the content of the disc but the license to view the content. Decrypting DRM is illegal not based on whether you own the content but because the DRM encryption itself is separately copyright protected.
You just reiterated what I said.
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Technically, if the FBI were to ask you to prove ownership of a digital copy and you had lost the disc, it would be illegal to retain that digital copy.
Yes. The Digital Millennium Copyright Act is a law that covers copyright protections.