> There is no constitutionally-enumerated power for Congress to regulate which character-encoding standard is used.
If you squint, it's kind of covered by the weights and measures clause, in the same way that the clause that allows Congress to establish armies covers Congress establishing the Air Force.
You don't really need to squint. A combination of the weights and measures clause, the interstate commerce clause, the federal postal service, is more than enough for Congress to have jursidiction on how names are to be encoded and processed.
If you squint, it's kind of covered by the weights and measures clause, in the same way that the clause that allows Congress to establish armies covers Congress establishing the Air Force.