Oppenheimer and the resurgence of Blu-ray and DVDs: How to stop your films and music from disappearing::In an era where many films and albums are stored in the cloud, “streaming anxiety” is making people buy more DVDs, records – and even cassette tapes.
They do not require any online connection. AACS has some ability to revoke media player keys, but it does so by encrypting future releases in such a way that the revoked player can not decrypt them (how this works technically is a bit complicated).
So if they decide to revoke your player, it can still play every Blu-ray disc manufactured before the revokation went into effect.