I don’t think manufacturers with deliberately undocumented, nigh-impossible-to-inspect crypto get to claim their bugs are shallow and thus that the absence of evidence for bugs implies the absence of bugs.

Less emotionally but mostly equivalently, the expense and non-cryptographic skill requirements of breaking mass-storage crypto are quite high while the rewards are comparable to those from breaking much softer targets, so the absence of results since that one paper only changes my mind very slightly. Besides, we know plenty of examples of what these kinds of opaque, serious-business, pay-to-play environments produce: cellular crypto is an uninterrupted series of disasters, so is Wi-Fi, and the things that we do know about storage devices don’t point to an outstanding culture of cryptographic competence there either. Once you’ve done enough to slap an “OPAL” label on it (which says nothing about the internals), there’s just no competitive pressure to improve.

There is a right way to do all this, and it’s essentially what NICs do: allow the host to offload symmetric crypto to the device, but keep the results of said crypto accessible at any moment. And it’s not like there are even that many modes used in full-disk encryption, let alone ciphers.