The Polish Post actually introduced a system like this recently. It serves as boring technical infrastructure for government agencies which still need to send

The Polish Post actually introduced a system like this recently. It serves as boring technical infrastructure for government agencies which still need to send physical mail. Instead of each agency employing their own people to handle printing their mail and stuffing it in envelopes, they can just send it electronically to the post office, which will handle it far more efficiently. The eventual goal is to move most people to e-deliveries, which you're encouraged to set up when using government services online. For those who haven't done so, the letter will be printed as close to them as possible to save on delivery time and costs, regardless of where in the country the sending agency is located.