> We shouldn't expect infinitely durable things to emulate tangible things that wear out because it would be convenient for rights holders if it were so.
Not only that, it's copyrights which are supposed to expire. The idea that physical media should be expected to degrade through the passage of time sooner than works will enter into the public domain is absurd.
After the copyright expires it's no longer a copyrighted work and then you're not circumventing DRM that protects a copyrighted work.
The real problem is that circumvention tools are prohibited regardless of what you use them for, so then they use the same DRM system on works that are still under copyright and you nominally can't provide someone with tools to break the DRM on the ones in the public domain. (In practice people just ignore the law or distribute circumvention tools from servers in other countries.)
It's not completely obvious that it actually works this way. For example, if someone's "DRM system" is that the box it comes in is screwed shut and you're intended to use some I/O pins provided on the outside, does that mean a screw driver is a circumvention tool and therefore screw drivers are illegal? Obviously problematic if so, but in the reverse case where anyone else using the same system for something other than protecting a copyrighted work means anyone can distribute tools to circumvent it, third parties would just put public domain works behind the same DRM system as copyrighted ones so that anyone could distribute circumvention tools. The prohibition on circumvention tools is batshit crazy.
So for example, if a diligent company offered a DRM removal tool, perhaps in escrow, for its media for which copyright had expired, it would be breaking the DCMA. Can DRM media be considered to be in the public domain if it is locked up by a company that’s probably out of business by the time copyright has expired, and breaking the encryption is illegal under DCMA? If the company is still in business, I suppose they could publish the keys publicly
Not only that, it's copyrights which are supposed to expire. The idea that physical media should be expected to degrade through the passage of time sooner than works will enter into the public domain is absurd.