The HIPAA final rule mandates ASC X12 as the standard format for certain interactions such as eligibility and claims. It's old and somewhat clunky, but it's not terribly hard to implement. Libraries are available for most popular languages. Even if we replaced X12 with a modern format like HL7 FHIR (which is now legally allowed for some interactions such as prior authorization) that wouldn't solve the fundamental business, legal, and clinical problems.