However, by a long series of deliberate actions, Stripe has made it irrelevant to the fact that they are now deliberately, unilaterally, and with zero notice whatsoever shutting down that biz' critical infrastructure.

They could have, and should have as a part of KYC compliance, already figured out what type of business it is. If they failed at that, then fine, give them 60 days notice to find other infrastructure. Stripe is taking its OWN FAILURE to properly vet their customers according to their own standards and dumping the consequences onto the ex-customers. Sorry, but unless we're talking actual provable international criminal/autocratic money-laundering, that's just wrong.