>> I really can’t think of something more reliable and cheaper with assurances of availability like this> Assurances that they only need because they're breaking the law. It is well established that blockchains are good to facilitating illegal behavior. This is just a novel way of using them for that purpose
I don't think that describing the mechanisms as facilitating illegal behavior is entirely fair. A better term would be something like "extralegal", which includes illegal behavior as a significant subcategory.
This isn't just sophistry. A significant fraction of the world's population live in places where "rule of law" is at best a polite fiction, or where the legal system is largely captured by a kleptocratic oligarchy[0].
It would be nice if trustless distributed ledgers were actually being used to do things like establish property rights and facilitate transactions in places that don't have, for example, a functioning land registry or the equivalent, or at least be shown to be useful to bootstrap that sort of thing into existence (collectible NFTs and virtual real estate are only baby steps in that direction), but it is true that the 'good' edge cases of establishing immutable ground truths that cannot be erased by fiat/regime change/interregnum are legitimate though largely theoretical[1].
Meanwhile, we're left with the definition of "facilitating behaviors that a court can be convinced to disallow, which are mostly, though not entirely, behaviors that are (and most citizens would agree should be) illegal". I can't think of a better concise term than "extralegal" to capture that nuance.
[0] I personally don't subscribe to the belief that this describes most of the industrialized world, whatever some cryptocurrency boosters think, but that's a political matter. Everybody draws the line somewhere, and agrees that some chunks of the world exist on the other side of it.
[1] Cryptocurrencies can also facilitate otherwise legal transactions that are being hindered by extralegal means, such as donations to WikiLeaks during the global payment processor blockade (December 2010 to July 2012).