Here in the Czech Republic, the national postal service does offer a "digital snail-mail" or "bureaucratic email" and it's used for official communication by go

Here in the Czech Republic, the national postal service does offer a "digital snail-mail" or "bureaucratic email" and it's used for official communication by government branches, insurance companies and some big companies. Nobody wants to use it for simple receipts, because messages are paid. A centralised service like this from a traditional company (so no VC-backed company with a generous free tier) just can't compete against the "simplicity" of sending email.