Format shifting has a DMCA carveout. It is 100% allowed. Since around 2000, the rule has permitted it for:
> Literary works, including computer programs and databases, protected by access control mechanisms that fail to permit access because of malfunction, damage, or obsoleteness.
DRM being covered under other laws, and being gross, still applies. And still applies to industry giants, too. Which is why most who do this, like Google, actually buy physical copies and scan it destructively, so they don't have to deal with it.
Yes, it's legal to format-shift DRM protected media, but it is not lawful. Someone has to break the law to provide me with a decryption tool.
If you asked the right politician when all these rules were being written, the intent was that each person who needs to format-shift their media would independently write their own decryption tools, use them for lawful purposes only, and then dutifully delete them the moment they were no longer needed. This is, of course, laughable.
Of course, if Anthropic was, say, buying and decrypting Kindle books TODAY; they probably could get Claude to vibe-code a DRM decryption tool[0]. That would actually be within the bounds of this asinine law. If Anthropic started off by doing this, however, they probably would have just used a decryption tool found on the Internet, and that would have invited different legal challenges. Like, is it legal to use an unlawful tool to accomplish something otherwise legally protected? The courts so far have been very hostile to ANY attempt to tie the anticircumvention provisions of the DMCA to fair use. They could easily say "No, you only get to format shift with your own tools".
[0] Related note: I really wish I had Mythos access, just so I could jailbreak my iPad on modern iPadOS. No other reason.