I'm fascinated that you'd choose optical discs when you're into preservation, given how famously vulnerable they are to scratches. What's your thinking here?
To me, the ability to own your data has nothing to do with which type of disc you store it on. That's purely about whether you buy or download DRM-free files. You can obviously "own" a great many more things on a 5TB NAS in your living room than you can on CDs. No-one can take that away either.
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